Have avoided bringing this up for years but its time i tell you all this “The Taproot system anchors the plant more firmly than the fibrous root . Fibrous root system anchors less efficient than taproot. The absorption of water and minerals by taproot is more efficient with the taproot system. Fibrous root absorbs water more efficiently as it reaches deep into the soil.” Some of you right now are thinking yes we know and others realize rootstocks are fibrous roots. I’m bringing this up because it is better if you can grow a tree in place or preserve its tap root when you dig it up. A friend once said yes i would have dug out the tap root but the tap root was 8 feet long. The tap root is long for a reason the more you dig out the better your tree will do.Taproot - Wikipedia
Many years farming using modern Agriculture techniques have been around leaving the top several feet of soil fairly depleted of nutrients. A tap root reaches down where the modern farmer couldn’t which is why a full sized tree will always be superior in nutrients and we will always get more nutrients from its fruit. Modern growers do not want to do a laser burn on their dwarf fruit versus my full sized fruit to determine nutrient content. Once a pear ages it’s fruit tastes better because the roots spread out it has more nutrients. When a pear first produces most of the time but not always the fruit is poor quality. Literally I can taste the difference and so can many other people. There is no proof ofcourse yet and its not a fact until its proven that nutrient levels are higher.
It’s interesting that in wine it’s well recognized that old vines (with insanely well established roots) produce a higher quality of wine. I think a lot of people do recognize that the first year or two of production in many fruits won’t reach the full potential, but many of us don’t think beyond that to the idea of fruit quality continuing to improve over following decades (assuming the trees actually have resources to tap into - where I’m at I need to give calcium to my apple trees since we simply don’t have sufficient levels in our soil even for old trees).
Yes people are very naive to the fact apple trees use lots of calcium for their fruits in general. Since you know that it tells me where you are from. It would be like if you told me you had got a terrible rash from your cashews immediately I have ideas of the location as only they would know that.
The calcium is essential for tree structure too. I have a wild seedling apple that has been plagued by canker for its entire life by the looks of it. A number of years back I gave it a generous supplement of crushed oyster shells and all the new growth since then has been virtually canker free in addition to a huge improvement in fruit quality, productivity and even reduced pest load.
Just to review Plant Morphology 101 in a few words (therefore, leaving out a lot).
The first root to emerge from a seed is the taproot. In some plants (both woody and herbaceous), it grows to form a main taproot and a multitude of branch roots that form the taproot system. If you cut roots of the taproot system, additional branch roots will form. If the main taproot proper is severed, other taproot system roots will grow downward to replace its function. The plant will then have one or more roots replacing the taproot. This is typical of woody plants.
On the other hand, the taproot of many herbaceous plants dies shortly after emergence. Before the taproot’s death and thereafter, a multitude of new roots arising from the base of the stem emerge and replace the dying taproot. They are called adventitious roots because they arise from a stem and not from a root. These adventitious roots form what is called a fibrous root system. Grasses are an excellent example of a plant with a fibrous root system.
Branches from a taproot system (root from root, and not root from stem) NEVER form a true fibrous root system. All roots branching from the taproot system are part of the taproot system and are not a fibrous root system. Blueberries have a very fibrous, shallow taproot system and NOT a true fibrous root system. Taproot systems can form a fibrous network, but it is not a true fibrous root system.
When a cutting of a woody plant (remember, woody plants have a taproot system) is taken, the roots arising from that stem cutting are adventitious roots (roots arising from stems or leaves), but they do not grow into a fibrous root system. The roots of fibrous root systems do not grow larger and larger in diameter like the roots of the woody plant cutting will. You don’t see that happening in grasses because they have a true fibrous root system. Dandelions would be an exasperating example of an herbaceous plant with a storage taproot system.
To put it another way, the taproot is the first root front the seed. It also called the primary root. Roots that branch from the primary root are known as lateral, or secondary, roots. Once the taproot (primary) root is cut, no more taproot. BUT, lateral roots will take over the functions of the taproot.
So, your take on cloned apple rootstocks such as M9 or G11 or B10 is?
Some of them never reach as deep or broad as a bushel basket.
This is correct when making rootstock clonal cuttings the roots might be 3 or 4 growing down instead of 1. My experience is at least short term they don’t go as deep at least as fast as a tree grown from seed. A tree grown from seed if all else is equal grows down very fast. Have no way to know if after 15 years they eventually catch up growing downward but my opinion is its never the same.
Besides anchorage, the main function of “taproots” is to reach water- the vast majority of soil nutrient absorption by trees is done in the top few inches of soil where the soil is almost always richer in nutrients and airy and warm enough for them to function efficiently, although, if soil below has nutrients unobtainable above, roots will forage by growing where they need to to get essential nutrients unavailable above or through mycorrhizal contributions. However, how much of this is occurring even in tired farm soil would be difficult to know- in most soils the only nutrient that creates a measurable response in established trees is nitrogen, indicating they are pretty much getting what they need of everything else.
For fruit trees some nutrients besides N are removed beyond the capacity of soils to replace, of course.
The most impressive taproots are created by desert plants such as mesquite trees whose roots have been found as far a 150 feet below ground. In my region it has been observed that maple trees extract water from deep roots during drought and when capillary pull declines and stops as the sun goes down water is is pulled down by gravity from the vascular system and released by roots located in the top soil, apparently to help the trees get access to that more nutritious soil by putting water there. It also helps other plants in the area withstand drought.
Carl Whitcomb has established that by forcing trees to focus on developing fibrous roots by starting in pots that “prune” tap roots, trees grow with more vigor. I assume they can regenerate tap roots again once they begin to establish in their permanent growing sites.
It’s almost as if you’re describing central leader versus open vase or other pruning styles 
My understanding was similar with the exception that the water deep in the soil was heavily mineralized. Think about hard water and the minerals it contains. As an example an oaks leaves are very high in calcium but there is no calcium at the top 3 feet so where does it come from? I believe there is bedrock down there and water and the hard water is sucked up like a straw then dispersed in the tree. Over time the calcium is added back into the top layer of soil as trees lose their leaves every year falling to the ground. Forest soil growing beside my grass soil is far richer soil. The grass is able to absorb the nutrients in the top several feet but cannot go deeper.
The Tree and The Soil
This article is very interesting Effect of species on macro and micro mineral composition of oak leaves with respect to sheep requirements
" The aim of the current study was to determine the effect of species on the macro and mineral composition on the oak tree leaves used for small ruminant animal in Turkey.
Calcium contents of oak trees ranged from 8.32 to 8.67 with highest being for Quercus cerris and lowest for Quercus branti. Phosphorus content of oak tree leaves varied widely from 3.06 to 3.38 g/kg DM with highest being for Quercus branti and lowest for Quercus coccifera. Magnesium contents of oak species ranged from 2.34 to 2.54 g/DM with highest being for Quercus branti and lowest for Quercus coccifera. Potassium contents of oak trees ranged between 10.93 to 11.91 g/kg DM, the lower value corresponding to Quercus cerris and the higher to Quercus libani. There were significant differences among oak species in terms of Iron contents which varied between 264.7 to 291.3 mg/kg DM, the lower value corresponding to Quercus libani and the higher to Quercus branti. There were significant differences among oak species in terms of Zinc contents which varied between 32.5 to 41.1 mg/kg DM, the lower value corresponding to Quercus cerris and the higher to Quercus suber. Species had a significant effect on the macro and micro mineral composition of oak tree leaves. All oak species had a significant amount macro and micro minerals to support the growth and production of lamb and sheep.
Key words: macro mineral, micro mineral, sheep, oak tree leaves
Introduction
It is well known that tree leaves play important role for small ruminant animals in providing with energy, protein and mineral for growth in the most parts of world (Kamalak et al 2010; Kaya and Kamalak 2012). Oak is one of the most important trees which provide considerable amount leaves and acorn for ruminant animals to meet their requirements. There are a lot of oak trees from different species in Turkey. Although there are a lot of researches carried out on the chemical composition, nutritive value of oak tree leaves in terms of metabolisable energy and organic matter digestibility (Kamalak et al 2004; Ozkan and Sahin 2006; Kilic et al 2010), the mineral content of oak tree leaves from different species was ignored by researches and thus, there is limited research on the macro and micro mineral contents of oak species such as Q. infectoria, Q. cerris, Q. coccifera, Q. libani, and Q. suber. Macro and micro minerals may have important role as a structural function in bones, as electrolytes in body fluids, as integral components of enzymes and other biologically important compounds (Bourne and Orr 1988). The information about macro and micro mineral compositions of oak tree leaves from different species can be used in accurate formulation of diet to achieve the optimum performance of small ruminant animals. The aim of the current study was to determine the effect of species on the macro and mineral composition on the oak tree leaves used for small ruminant animal in Turkey.
Materials and Methods
Tree leaves
Oak leaves from Q.branti, Q. infectoria, Q. cerris, Q. coccifera, Q. libani, and Q. suber were collected in July, 2014 by hand from eat least 10 different trees of each oak species in Kahramanmaras, Turkey (Figure 1). The soil of the study area is classified as Inceptisols which was formed on a colluvial serpentine-limestone parent material (Yilmaz et al 2000 ). Oak species of Q. infectoria, Q. cerris, and Q. libani, are deciduous with leaf life span between 5-6 months (approximately) whereas oak species of Q. coccifera and Q. suber are evergreen with a leaf life span 15 and 15.6 months (Mediavilla et al. 2008).
Figure 1. Location of Kahramanmaras Province in Turkey (Wikipedia)
Leaf samples were pooled and dried at 65 0C using a forced air oven. Dried oak leaves were ground using a laboratory mill with 1 mm screen size for mineral analysis. Oak tree leaves were subjected to wet-ashing process with hydrogen peroxide following three different steps. Firstly oak leave samples were kept at 145 ºC 75% microwave power for 5 minutes. Secondly oak leave samples were kept at 80 ºC 90% microwave power for 10 minutes. Finally oak leave samples were kept at 100 ºC 40% microwave power for 10 minutes in a wet-ashing unit (speed wave MWS-2 Berghof products + Instruments Harresstr.1. 72800 Enien Germany) resistant to 40 bar pressure (Mertens 2005a). After wet-ashing, macro and micro mineral contents of oak tree leave samples were analyzed using Inductively Couple Plasma Optical Emission Spectrophotometer (Perkin-Elmer, Optima 2100 DV, ICP/OES, Shelton, CT 06484-4794, USA) (Mertens 2005b).
Statistical analysis
One-way analysis of variance (ANOVA) was used to determine the effect of species on the macro and mineral composition on the oak tree leaves. Significance between individual means was identified using the Tukey’s multiple range tests. Mean differences were considered significant at P<0.05.
Result and Discussion
Macro mineral contests of oak tree leaves
Effect of species on the macro mineral composition of oak tree leaves is given in Table 1. Species had a significant effect on the macro mineral composition of oak tree leaves. Calcium contents of oak trees ranged from 8.32 to 8.67 with highest being for Q. cerris and lowest for Q. branti. The Ca contents of Q. coccifera and Q, infectoria are consistent with finding of Gokkus et al (2011) who reported that Ca contents of Q. coccifera and Q. infectoria varied from 5.9 to 12.7 and 2.8 to 17.2 g / kg DM respectively. The Ca contents of Q.cerris is in agreement with findings of Leonardi et al (1999) who reported that Ca contents of Q. cerris was 9.2 g/kg DM. NRC (1985) suggested that calcium contents in the range of 0.2 and 0.82 % of DM are adequate for lamb and sheep at gestation and lactation stages respectively. As can be seen from Table 1, calcium contents of all oak species studied in the current study were higher than the upper value reported by NRC (1985).
Phosphorus content of oak tree leaves varied widely from 3.06 to 3.38 g/kg DM with highest being for Q. branti and lowest for Q. coccifera. Phosphorus contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2011) who reported that P contents of Q.coccifera and Q. infectoria varied from 1.38 to 3.74 and 2.09 to 4.33 g/ kg DM respectively. The P contents of Q. cerris is in agreement with findings of Leonardi et al (1999) who reported that P contents of Q. cerris was 2 g/kg DM. NRC (1985) suggested that phosphorus contents in the range of 0.16 and 0.38 % of DM is adequate for lamb and sheep at most production stages. As can be seen from Table 1, phosphorus contents of all oak species studied in the current study were higher than the upper value reported by NRC (1985).
Magnesium contents of oak species ranged from 2.34 to 2.54 g/DM with highest being for Q. branti and lowest for Q. coccifera. Magnesium contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2011) who reported that Mg contents of Q. coccifera and Q. infectoria varied from 2.39 to 2.85 and 2.63 to 3.55 g/kg DM respectively. The Mg contents of Q. cerris is in agreement with findings of Leonardi et al (1999) who reported that Mg contents of Q. cerris was 2.1 g/kg DM. Although there is limited information about requirement of magnesium for sheep, NRC (1985) suggested that the minimum requirement of magnesium should be 0.12, 0.15 and 0.18 g/kg DM for growing lamb, pregnant and lactating ewe respectively. As can be seen Table 1, magnesium contents of all oak species were higher those suggested by NRC (1985) for growing lamb, pregnant and lactating ewe.
Potassium contents of oak trees ranged between 10.93 to 11.91 g/kg DM, the lower value corresponding to Q. cerris and the higher to Q. libani. Potassium contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2011) who reported that K contents of Q. coccifera and Q. infectoria varied from 4.22 to 14.02 and 2.98 to 12.81 g/kg DM respectively. The K contents of Q. cerris is in agreement with findings of Leonardi et al (1999) who reported that K contents of Q. cerris was 8.9 g/kg DM. Although potassium content of diets for lamb growth should be more than that 0.5 % of DM, the potassium content of diets for lactating sheep should be in the range of 0.7-08 of DM (NRC 1985). As can be seen Table 1, potassium contents of all oak species were higher those suggested by NRC (1985) for lamb and sheep.
There were also significant differences among oak species in terms of sodium content which ranged between 1.24 to 1.50 g/kg DM, the lower value corresponding to Q. branti and the higher to Q. suber. Sodium contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2013) who reported that Na contents of Q. coccifera and Q. infectoria varied from 0.57 to 0.85 and 0.68 to 1.44 g/kg DM respectively. The sodium contents in the range of 1 to 4 g/kg DM are adequate for sheep at most production stages (Underwood 1981). Sodium contents of all oak species studied in the current experiment fell into this range. Therefore it is not likely that sodium deficiency will occur with sheep consuming oak trees from different species.
Table 1. Effect of species on the macro mineral composition (g/kg DM) of oak tree leaves (n=3)
Oak species Macro minerals
Ca P Mg K Na
Quercus branti 8.32f 3.38 a 2.46a 11.67d 1.24e
Quercus infectoria 8.52c 3.19bc 2.34e 11.32e 1.24e
Quercus cerris 8.67a 3.12cd 2.35d 10.93f 1.30d
Quercus coccifera 8.41e 3.06d 2.32f 11.78c 1.39c
Quercus libani 8.52d 3.06d 2.45b 11.91a 1.44b
Quercus suber 8.65b 3.28ab 2.41c 11.81b 1.50a
SEM 0.001 0.038 0.001 0.001 1.18
p <0.001 <0.001 <0.001 <0.001 <0.001
abc Column means with common superscripts do not differ (P>0.05); SEM: Standard error mean
Micro mineral contests of oak tree leaves
Effect of species on the micro mineral composition of oak tree leaves is given in Table 2. Species had also a significant effect on the micro mineral composition of oak tree leaves. There were significant differences among oak species in terms of Iron contents which varied between 264.7 to 291.3 mg/kg DM, the lower value corresponding to Q. libani and the higher to Q. branti. Iron contents ofQ. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2013) who reported that Fe contents of Q. coccifera and Q. infectoria varied from 75.1 to 236.7 and 122.3 to 346.2 mg/kg DM respectively. NRC (1985) suggested that 30 mg /kg DM is adequate to meet the dietary iron requirements for all classes of sheep. On the other hand, a maximum tolerable level of Fe has been indicated as 500 mg Fe/kg DM (NRC 1980). As can be seen from Table 2, Fe contents of all oak species studied in the current experiment was eight or nine times higher than that reported by NRC (1985) but lower than maximum tolerable level suggested by NRC (1980).
There were significant differences among oak species in terms of Zinc contents which varied between 32.5 to 41.1 mg/kg DM, the lower value corresponding to Q. cerris and the higher to Q. suber. Zinc contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2013) who reported that Zn contents of Q. coccifera and Q. infectoria varied from 17.31 to 33.93 and 22.44 to 30.47 mg/kg DM respectively. Although zinc requirement of lamb for growth is 20 mg/kg DM, zinc requirement of sheep at most production stages is 33 mg /kg DM. The zinc contents of different oak trees are higher than the adequate level of Zinc. Therefore sheep fed on different oak tree species is not likely to suffer from zinc deficiency.
Copper contents of oak tree leaves varied widely from 36.7 to 48.3 mg/kg DM with highest being for Q. infectoria and lowest for Q. coccifera. Copper contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2013) who reported that Cu contents of Q. coccifera and Q. infectoria varied from 4.75 to 15.37 and 5.93 to 113.78 mg/kg DM respectively. It is very difficult to give the exact dietary copper requirement of sheep since there are some factors affecting dietary copper requirement of sheep. There are considerable differences among sheep breeds in terms of efficiency in absorbing copper from feedstuffs. On the other hand, the amount of molybdenum in feedstuffs also effect of the dietary copper requirement of sheep. High level of molybdenum in feedstuffs induces the copper deficiency. However the copper contents of oak species is adequate for sheep since the copper contents of oak species higher than that (7-23 mg/kg DM) recommended by NRC (1985).
Table 2. Effect of species on the micro mineral composition (mg/kg DM) of oak tree leaves(n=3)
Oak species Micro minerals
Fe Zn Cu Mn
Quercus branti 291.3a 39.6b 40.2d 82.8a
Quercus infectoria 274.3c 35.1e 37.1e 76.2b
Quercus cerris 282.3b 32.5f 36.7f 72.1d
Quercus coccifera 283.7b 36.4d 48.3a 70.8e
Quercus libani 264.7e 37.3c 48.0b 67.5f
Quercus suber 267.7d 41.1a 46.1c 76.2b
SEM 0.81 0.04 0.01 0.02
p <0.001 <0.001 <0.001 <0.001
abc Column means with common superscripts do not differ (P>0.05); SEM: Standard error mean
Manganese contents of oak tree leaves ranged from 67.5 to 82.8 mg/kg DM with highest being for Q. branti and lowest for Q. coccifera. Manganese contents of Q. coccifera and Q. infectoria are consistent with finding of Gokkus et al (2013) who reported that Mn contents of Q. coccifera and Q. infectoria varied from 71.2 to 314.6 mg and 552.5 to 1569 mg/kg DM respectively. Although exact dietary requirement of manganese for sheep is not known, 20 mg/kg DM of manganese should be adequate for sheep at most production stages (NRC 1985). Therefore manganese contents of oak trees from all oak species were three or four times higher than that adequate level for sheep at most production stages.
Conclusions
-
Species had a significant effect on the macro and micro mineral composition of oak tree leaves.
-
All oak species had a significant amount macro and micro minerals to support the growth and production of lamb and sheep.
References
Bourne R A and Orr R M 1988. Animal physiology and nutrition. In: R.J. Halley and R.J. Soffe (eds). The Agricultural Notebook. Blackwell Scientific Publication. Oxford, UK.
Gokkus A, Parlak A O and Parlak M 2011. Change of mineral element content in the common shrubs of Mediterranean zone. I. Macronutrients. Agriculture, 98(4), 357-366. lzi.lt
Gokkus A, Parlak A O and Parlak M 2013. Change of mineral element content in the common shrubs of Mediterranean zone. I. Micronutrients. Ege Univiersitesi Ziraat Fakültesi Dergisi, 50(1),409-418. http://egeweb.ege.edu.tr/zfdergi/edergiziraat/2013_cilt50/s1/12.pdf
Kamalak A, Canbolat O, Atalay A I and Kaplan M 2010. Determination of potential nutritive value of young, old and senescent leaves of Arbutus andrachne tree. Journal of Applied Animal Research, 37, 257-260. http://www.tandfonline.com/doi/pdf/10.1080/09712119.2010.9707136
Kamalak A, Canbolat O, Ozay O and Aktas S 2004. Nutritive value of oak (Quercus spp.) leaves. Small Ruminant Research, 53, 161–165. http://www.sciencedirect.com/science/article/pii/S0921448803003298
Kaya E and Kamalak A 2012. Potential nutritive value and condensed tannin contents of acorns from different oaks species. Kafkas Universitesi Veteriner Fakultesi Dergisi, 18(6), 1061-1066. http://vetdergi.kafkas.edu.tr/extdocs/2012_6/1061-1066.pdf
Kilic U, Boga M and Guven I 2010. Chemical composition and nutritive value of oak (Quercus robur ) nut and leaves. Journal of Applied Animal Research, 38, 101-104. http://www.tandfonline.com/doi/pdf/10.1080/09712119.2010.9707165
Leonardi S, Failla M, Sciacca G and Rapp M 1999. Above-ground biomass and nutrients in a Turkey oak (Quercus cerris L.) stand on Mount Etna. Oecologia, 8,1-5. http://www.vuvb.uniza.sk/ojs2/index.php/OM/article/viewFile/314/241
Mediavilla S, Garcia-Ciudad A, Garcia-Criado B, Escudero A. 2008. Testing the correlations between leaf life span and leaf structural reinforcements in 13 species of European Mediterranean woody plants. Functional Ecology, 22:787-793. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2435.2008.01453.x/pdf
Mertens D. 2005a. AOAC official method 922.02. In: Horwitz, W., Latimer, G.W. (Eds.), Plants Preparation of Laboratory Sample. Official Methods of Analysis, 18th ed. AOAC-International Suite, Gaitherburg, MD, USA, (Chapter 3), pp. 1–2.
Mertens D. 2005b. AOAC official method 975.03. In: Horwitz, W., Latimer, G.W. (Eds.), Metal in Plants and Pet Foods. Official Methods of Analysis, Official Methods of Analysis, 18th ed. AOAC International Suite, Gaitherburg MD, USA, (Chapter 3), pp.3.4
NRC 1980 . Mineral tolerance of domestic animals. National Academy of Sciences. Washington, D.C.
NRC 1985 Nutrient requirements of sheep. National Academy Press, Washington, D.C.
Ozkan C O. and Sahin M 2006. Comparison of in situ dry matter degradation with in vitro gas production of oak leaves supplemented with or without polyethylene glycol (PEG). Asian-Australian Journal of Animal Science, 19(8), 1120 – 1126. http://ajas.info/upload/pdf/181.pdf
Underwood E J 1981. The Mineral Nutrition of Livestock. Commonwealth Agricultural Bureaux. Slough, UK.
Yılmaz K , Gundogan R, Demirkıran AR. 2000. Pedogenesis and classification of soils in Kahramanmaraş Province, Turkey. International Symposium on Desertification, ISD, Proceedings p: 517-524. Konya, Turkey"
Your link provides no information about tap roots drawing calcium from the soil depths and a quick search didn’t help me find anything about it. Have you compared the pH of soil by the oaks to the soil that isn’t influenced by their leaves? That might provide your anecdote with some legs.
Yes the soil is notably more acidic in the wooded areas. Here is another study citing oaks as important to bringing up soil nutrients however its my own hypothesis that the tap root is where those nutrients are comng from. Nutrient Cycling in California - UC Oaks
" Are oak trees an important component for sustaining ecosystem productivity in California oak woodlands? A research project sponsored by the Integrated Hardwood Range Management Program examining nutrient cycling is showing that oak trees play a major role in maintaining the nutrient status of these ecosystems. Each year, a typical blue oak (Quercus douglasii) will return approximately 2, 1, 2.5, and 1.8 kg of nitrogen, phosphorus, calcium and potassium, respectively, to the soil surface in the form of litterfall (leaves, twigs and acorns) and canopy throughfall (canopy leaching). While these values may appear low, multiplying by all the oaks in a watershed results in very large quantities of nutrients.
Nutrients contained in litterfall are slowly released by microbial decomposition resulting in replenishment of nutrient pools beneath the oak canopy. Concentrations of major nutrients in the soil solution beneath an oak canopy are 2-10 times higher than in soil solutions in adjacent grassland soils indicating a more nutrient rich soil environment beneath the tree canopy.
The distribution of roots within the soil profile also plays an important role in nutrient dynamics. At the Sierra Foothill Range Field Station, annual grasses were observed to have the majority of their roots in the upper 30 cm of the soil profile while oak roots were found primarily at depths greater than 30 cm. In grassland soils, nutrients leached below the shallow rooting zone of annual grasses are removed from the ecosystem into stream or ground waters. In contrast, the deeply rooted oak trees are able to capture the majority of the nutrients before they are lost from the ecosystem by leaching. Therefore, removing oak trees from the ecosystem will result in a gradual loss of nutrients from the ecosystem through leaching losses.
This loss of soil nutrients is confirmed by studies examining forage production following oak tree removal. These studies consistently show increased forage yield immediately following tree removal due to removal of competition for nutrients, water, and light by the oak trees. However, forage yields show a steady decline following the initial peak and fall below pre-tree removal levels after approximately ten years. This indicates that the effects of oak trees on the soil nutrient status are short-lived following their removal and that nutrient reserves are quickly depleted by leaching.
Soils beneath the oak canopy are also characterized by having significantly higher organic matter concentrations due to annual litterfall returns (approximately 7000 kg/ha beneath blue oak trees). In addition to the positive effect of organic matter on the soil nutrient status, higher organic matter concentrations lead to lower soil bulk density and greater porosity. This in turn provides increased infiltration rates for rainfall which reduces surface runoff, water erosion and stream water sediment loads.
In conclusion, oak trees play a critical role in sustaining ecosystem productivity through their role in cycling nutrients to the soil surface, preventing nutrient leaching losses, increasing water infiltration, and attenuating water erosion and stream sediment concentrations.
Randy Dahlgren
prepared and edited by John M. Harper, Richard B. Standiford, and John W. LeBlanc
There are other discussions on the subject some dont know and many see it similar to how i do or the opposite. There is another important job of the tap root i should bring up which we know it stores nutrients. Tap roots have functions beyond anchoring which is why they were there to start with. How signifigant they are to the plant long term im not sure we know. Do the side roots compensate for the loss? We know the other roots attempt to compensate for a partially lost tap root.
https://www.researchgate.net/post/Which-roots-absorb-more-water-and-nutrients
Calcium would be evident by increasing the pH not reducing it. The replenishment provided by tree leaves, with the exception of carbon, comes entirely from the soil they are growing in, but carbon (OM) could be responsible for increasing the growth of grass as much as any “nutrient” (water is also a nutrient, of course) as it increases available water and the ability of soil to hold nutrients from leeching.
Your suggestion of the importance of tap roots bringing calcium up from the depths is not what I’d term a hypothesis. By my def, it is speculation. The former word is usually used as the first stage of an experiment to verify it. I’d find it more interesting if it was verified.
Have you ever heard the term “mining” tap roots mine the soil? Im aware calcium increases ph but the trees in my woods are not oak. Water and Nutrient Uptake . This was what we were looking for that appears to support my hypothesis based off my own observations. Roots | Biology for Majors II
" The roots of seed plants have three major functions: anchoring the plant to the soil, absorbing water and minerals and transporting them upwards, and storing the products of photosynthesis. Some roots are modified to absorb moisture and exchange gases. Most roots are underground. Some plants, however, also have adventitious roots, which emerge above the ground from the shoot.
Types of Root Systems
Root systems are mainly of two types (Figure 1). Dicots have a tap root system, while monocots have a fibrous root system. A tap root system has a main root that grows down vertically, and from which many smaller lateral roots arise. Dandelions are a good example; their tap roots usually break off when trying to pull these weeds, and they can regrow another shoot from the remaining root). A tap root system penetrates deep into the soil. In contrast, a fibrous root system is located closer to the soil surface, and forms a dense network of roots that also helps prevent soil erosion (lawn grasses are a good example, as are wheat, rice, and corn). Some plants have a combination of tap roots and fibrous roots. Plants that grow in dry areas often have deep root systems, whereas plants growing in areas with abundant water are likely to have shallower root systems.
Figure 1. (a) Tap root systems have a main root that grows down, while (b) fibrous root systems consist of many small roots. (credit b: modification of work by “Austen Squarepants”/Flickr)
Root Growth and Anatomy
Figure 2. A longitudinal view of the root reveals the zones of cell division, elongation, and maturation. Cell division occurs in the apical meristem.
Root growth begins with seed germination. When the plant embryo emerges from the seed, the radicle of the embryo forms the root system. The tip of the root is protected by the root cap, a structure exclusive to roots and unlike any other plant structure. The root cap is continuously replaced because it gets damaged easily as the root pushes through soil. The root tip can be divided into three zones: a zone of cell division, a zone of elongation, and a zone of maturation and differentiation (Figure 2). The zone of cell division is closest to the root tip; it is made up of the actively dividing cells of the root meristem. The zone of elongation is where the newly formed cells increase in length, thereby lengthening the root. Beginning at the first root hair is the zone of cell maturation where the root cells begin to differentiate into special cell types. All three zones are in the first centimeter or so of the root tip.
The root has an outer layer of cells called the epidermis, which surrounds areas of ground tissue and vascular tissue. The epidermis provides protection and helps in absorption. Root hairs, which are extensions of root epidermal cells, increase the surface area of the root, greatly contributing to the absorption of water and minerals.
Figure 3. Staining reveals different cell types in this light micrograph of a wheat (Triticum) root cross section. Sclerenchyma cells of the exodermis and xylem cells stain red, and phloem cells stain blue. Other cell types stain black. The stele, or vascular tissue, is the area inside endodermis (indicated by a green ring). Root hairs are visible outside the epidermis. (credit: scale-bar data from Matt Russell)
Inside the root, the ground tissue forms two regions: the cortex and the pith (Figure 3). Compared to stems, roots have lots of cortex and little pith. Both regions include cells that store photosynthetic products. The cortex is between the epidermis and the vascular tissue, whereas the pith lies between the vascular tissue and the center of the root.
The vascular tissue in the root is arranged in the inner portion of the root, which is called the stele (Figure 4). A layer of cells known as the endodermis separates the stele from the ground tissue in the outer portion of the root. The endodermis is exclusive to roots, and serves as a checkpoint for materials entering the root’s vascular system. A waxy substance called suberin is present on the walls of the endodermal cells. This waxy region, known as the Casparian strip, forces water and solutes to cross the plasma membranes of endodermal cells instead of slipping between the cells. This ensures that only materials required by the root pass through the endodermis, while toxic substances and pathogens are generally excluded. The outermost cell layer of the root’s vascular tissue is the pericycle, an area that can give rise to lateral roots. In dicot roots, the xylem and phloem of the stele are arranged alternately in an X shape, whereas in monocot roots, the vascular tissue is arranged in a ring around the pith.
Figure 4. In (left) typical dicots, the vascular tissue forms an X shape in the center of the root. In (right) typical monocots, the phloem cells and the larger xylem cells form a characteristic ring around the central pith.
Root Modifications
Figure 5. Many vegetables are modified roots.
Root structures may be modified for specific purposes. For example, some roots are bulbous and store starch. Aerial roots and prop roots are two forms of aboveground roots that provide additional support to anchor the plant. Tap roots, such as carrots, turnips, and beets, are examples of roots that are modified for food storage (Figure 5).
Epiphytic roots enable a plant to grow on another plant. For example, the epiphytic roots of orchids develop a spongy tissue to absorb moisture. The banyan tree (Ficus sp.) begins as an epiphyte, germinating in the branches of a host tree; aerial roots develop from the branches and eventually reach the ground, providing additional support (Figure 6). In screwpine (Pandanus sp.), a palm-like tree that grows in sandy tropical soils, aboveground prop roots develop from the nodes to provide additional support.
Figure 6. The (a) banyan tree, also known as the strangler fig, begins life as an epiphyte in a host tree. Aerial roots extend to the ground and support the growing plant, which eventually strangles the host tree. The (b) screwpine develops aboveground roots that help support the plant in sandy soils. (credit a: modification of work by “psyberartist”/Flickr; credit b: modification of work by David Eikhoff)"
There is nothing I see that suggests a study of specific nutrients mined from the deep by tree tap roots.
“Taproots on the other hand, consist of one or more large main root with smaller side roots. These head deep into the soil to search for water and nutrients. Examples of taproots include carrot and beet. Farmers and gardeners can use cover crops of taprooted plants to “mine” nutrients from deep in the soil. As the taproots take up these nutrients, they distribute them throughout the plant body. When the mature plants are tilled into the soil, the nutrients that they contain are incorporated into the topsoil-the region where most crop plants’ roots are concentrated.”
This article says more of the same " Finally, in regards to the root systems, there are two main types, tap roots and fibrous roots. Tap roots have one or two strong main roots that grow straight down with few branching roots coming off of them. This root system serves as a strong anchorage in loose soils and allows the plant to draw nutrients and water from deeper in the soil profile. Fibrous routs, on the other hand, generally grow close to the surface of the soil and are heavily branched; with no root becoming clearly prominent. This sort of root structure allows plants to intercept water and nutrients quickly before they are able to move deeper in the soil profile and acts to stabilize the soil around them."
They are not talking about deep tree tap roots, but I do see your point. However carrots and beets do not send down deep tap roots in the scale of trees.
If trees could draw meaningful calcium from deep in the soil, I would expect the fact would have long since been researched because of how important the implications would be from an ecological as well as agricultural perspective.
Orchardists in the NE spend a lot of money at many sites adding calcium every 3 years or so because it leeches from soils so quickly. Typical forest soils around here tend to be acidic.
@alan
The surface was farmed out from row cropping here. The lateral roots on pears no doubt can bring in nutrients as well but if you dig up the roots they all have smaller roots on them as they go down. Why If not for nutrient absorption would they have those? It’s not even really a hypothesis more of a fact if I go by appearance. The tap root is for anchoring and water as well but we know what those nutrient absorbers do. If you think about a trees roots what sense would it make for only the top small root hairs to absorb nutrients but not the bottom?
Here is another great article Caring for Plant Roots: What You Need to Know - FineGardening
" Article
Caring for Plant Roots: What You Need to Know
Watering, propagating, and feeding your plants successfully all depend on what they have going on belowground
By Steven Tjosvold Fine Gardening – Issue 174
Roots are often overlooked by gardeners but deserve to get more attention. Of course, they are usually underground and out of sight, so it’s somewhat understandable why they are largely ignored. But roots play a critical role in the life of a plant. They anchor the plant to support the shoots above. They absorb water and mineral nutrients and conduct them upward. They store carbohydrates and other nutrients that are a source of energy for woodies, perennials, and biennials as they awaken and grow in spring. Knowing the structure, configuration, and function of your plants’ roots can help you understand how to optimize plant propagation, irrigation, fertilization, and placement in the garden.
Get Familiar with the Anatomy of a Root
There’s a lot going on at the tip. The very end of a root is where most of the activity takes place in regard to finding and absorbing water and nutrients for the plant.
Understanding how roots form and grow is the key to understanding things like why a plant isn’t becoming more robust or why it may have tipped over in a windstorm. A root’s tip is where most of the action takes place, although it is structurally and functionally simplistic. The root tip has overlapping zones: where cells divide, elongate, or form different specialized cells. At the very tip, the root cap protects the rapidly dividing cells known as the meristematic region or meristem (zone of cell division). Behind the meristem, cells elongate and push the meristem and root cap forward into the soil so that the root can explore and mine new soil (zone of elongation). Farther back, only a fraction of an inch, is the portion where elongation stops and cells become more specialized and functional (zone of differentiation).
Root hairs form in the zone of differentiation; this is also where they begin to poke out into the soil to absorb water and mineral nutrients. Root hairs greatly increase the root surface area and therefore increase the ability of a plant to absorb water and nutrients. Vascular tissue is the next area of interest (vascular cylinder); it conducts water and nutrients upward through the core of the root. The epidermis is the final layer of cells and forms the skin of the roots. Water is absorbed through epidermal cells, too. In most woody plants, absorption is further increased by mycorrhizae, fungi that live in symbiotic association with roots. Lateral roots emerge from the core of the root, each complete with a root cap, meristem, root hairs, and all other basic root parts. The arrangement and spread of these clusters of roots determine the type of root system a plant has.
The type of root system dictates how you treat a plant
Plants may have two generalized root systems: fibrous and tap. A fibrous-root system consists of several to many main roots that branch frequently into a dense, shallow mass. Grasses as well as many annuals have fibrous-root systems. These root systems can help hold the soil together and prevent surface soil erosion. For instance, a single 20-inch-tall ryegrass plant may have an underground surface area of 1,890 square feet. With so many roots, fibrous systems are extremely efficient at absorbing water and mineral nutrients from the shallow portions of soil.
Fibrous-root system
- Type of plants: Most ornamental grasses and annuals, some perennials.
- What it looks like: Dense, mat-like networks of roots that reside in the first few inches of soil.
How to care for it: Once established, more frequent watering but using less water; lighter fertilizer application; simple division.
Once a plant is established, the best way to nurture this shallow but efficient root system is by targeting the root zone with more frequent watering but generally using less water each time in comparison to a tap-rooted plant. This is because you don’t need the water to soak deeply into the soil, because there aren’t any roots there. The same holds true when feeding plants with fibrous systems; keep the fertilizer applications light because the nutrients will be absorbed only within the first few inches of soil. Division is easy with these plants and can generally be done by digging out a portion of the plant with a small section of the root system intact.
Tap-root systems, in contrast, have one main root from which smaller lateral roots branch (bottom illustration, facing page). Many common perennials, such as baptisia (Baptisia spp. and cvs., Zones 3–9), young trees including some pines (Pinus spp. and cvs., Zones 2–9), and even dandelions, have tap roots. Additionally, root vegetables such as carrots, beets, parsnips, and radishes have tap roots that store a significant reserve of food and nutrients. Young trees and shrubs have tap roots that explore and mine deeper portions of the soil where water is more likely found, which can help these plants persevere through drought conditions better than plants with fibrous systems. A deep tap root can also help quickly anchor a plant. They therefore can stabilize a deep section of soil and prevent erosion in windy areas or sandy soil.
Tap-Root System
- Type of plants: Many nonwoody perennials, seedlings, or young woody plants.
- What it looks like: One main root with smaller lateral branching roots. Deeper rooted than fibrous roots.
How to care for it: Once established, use more water, but less frequently; heavier fertilizer application; do not divide.
Plants with tap roots, however, can be difficult to transplant, especially when they’re bareroot or balled-and-burlaped because these plants do not bind soil well, leaving the roots more exposed and prone to damage. Growers sometimes undercut (trim the main tap root down while still growing in the propagation field) to stimulate lateral root branching well before they are dug out of the ground to sell. When compared to fibrous systems, an established tap-root system should get less frequent watering (targeted at the root zone) but with more water at each irrigation, along with heavier fertilizer applications, when needed. This is so the water and nutrients can reach all the way down to the fast-absorbing root hairs. With little exception, plants with tap-root systems shouldn’t be divided, because you can’t split the main root. Instead, propagate them by cutting or seed.
Placement may depend on how the system matures
Most nonwoody plants have one generalized root system (fibrous or tap) throughout the entire life of the plant. Woody plants, however, might start with a tap-root system but become more complex as they grow and develop. For example, the tap root of a young oak tree (Quercus spp. and cvs., Zones 2–9) is usually well formed and especially important for getting established. In most mature oaks as well as other mature trees, however, the tap root is eventually outgrown by other major downward and horizontal roots. For all root forms, the root configuration and depth change depending on soil characteristics and watering, too. For instance, the fibrous root systems of a perennial will stay shallow in soils that do not have good drainage or if watering is always applied too shallowly and frequently. With all root forms, the goal in watering is to move moisture just beyond the root zone, both laterally and deeply. This ensures that all the root hairs get a drink.
Sometimes root systems can clash. Planting fibrous-rooted turfgrass or a carpet of petunias at the base of a young tap-rooted tree can suck water away from the woody plant, leaving it to struggle.
In a typical garden, you’ll likely mix plants with different root-system types. You’re probably thinking more about how this plays out aboveground (with the creation of compelling color or texture combinations), but it also has implications belowground. Interplanting shallow fibrous and deeply tap-rooted plants can help fully use (think layering of plants) or stabilize the soil. On the other hand, be aware that sometimes mixing root systems can be a bad thing. Turfgrass or masses of annuals, for example, growing right around newly planted trees and shrubs can rob the soil of water and nutrients before they can move to the young trees’ deeper tap-root system. It’s generally a good idea to keep dense, fibrous-rooted plants away from young trees in particular. Keep a distance of 12 inches away from their trunks.
The next time you have a chance to examine the root system of a seedling, potted plant, or freshly dug plant, take some time to examine and ponder how important and amazing the roots are.
Don’t be Fooled by Other Types of “Roots”
There are a couple of other types of so-called root systems that don’t fit into the fibrous or tap-root categories.
Adventitious roots arise from stems or leaves, not other roots. One example of these can be seen on ivy (Hedera helix* and cvs., Zones 4–9). As the plant creeps along the soil surface, roots can arise from stems and penetrate the soil, extending their coverage. Cuttings can be propagated easily by rooting these stem pieces. Corn plants develop adventitious roots as well. They appear at the base of the plant for the purpose of keeping it upright.
Rhizomes are root look-alikes that are actually stems. These specialized stems grow horizontally at or just below the soil surface. Many grasses, some ferns, and perennials such as bearded iris (Iris spp. and cvs., Zones 3–10, pictured) have rhizomes. To propagate these plants, the rhizome is cut or broken into sections, and at least one lateral bud “eye” or shoot is included on each cutting.
Why You should Pay Special Care to the Root Hairs
Root hairs are formed just behind the tip of the root. They are long, thin, single-cell extensions from the root skin (epidermis). They profoundly increase the overall root surface area and connection with the soil, and they are responsible for absorbing water and mineral nutrients. Usually they are short-lived, functional for only several days or weeks. So as the root tip advances into virgin soil, new root hairs must continuously be formed.
It is important to keep root hairs healthy. The overall vigor of a plant can often be judged by looking at the condition of the root hairs. When you buy a plant at the nursery, remove the pot if possible and look for healthy, usually white, root tips and hairs. Chlorosis, which is caused by an iron deficiency, is often incorrectly blamed on high pH or low iron in the soil. But the root hairs might be to blame. Iron is tightly held by soil, so in order for young leaves to obtain sufficient iron, there needs to be sufficient absorption by the roots and root hairs. If roots are not actively growing and reforming, as when soil is cold in spring, iron might not be sufficiently mined and conducted to new leaves.
Steven Tjosvold is an environmental horticulture adviser for the University of California Cooperative Extension.
Photos: Danielle Sherry ; Jamain; Nemar74; Steven Tjosvold. Illustrations: Judy Simon"
Another interesting thing about roots is a callery is clearly more efficient at acquiring the needs for the tree in my soil than other rootstocks. When we were faced with a serious drought not one of my trees didn’t produce fruit on callery even those where the tap root had been cut. The neighbors pears and apples did not produce fruits but many were older trees. We both know it’s all about the roots. Nature has one rule which is survival of the fittest and callery pears are winning that fight in many locations as much as we might not like that at times. Callery appear to have superior roots in dry climates to ohxf rootstocks. During the severe drought none of the pears were normal sized they were all smaller fruits that year. My ohxf pears did not produce fruit on any trees that year. The reason I bring these things up is because I observe things I suspect may be things that happen 2 or 3 times in a lifetime. My blackberries I planted in pure Clay the soil is now nice looking black dirt on the top of that soil. Those blackberries mine that clay and get nutrients out of it other things have failed to extract but clearly don’t need tap roots to do that. They do not grow very much for the first 3 years but once they hit the water table they look good quickly. The water table is believed to be about 15 -20 feet down. No doubt when it rains the roots chase the moisture as it goes deeper in the earth until they find it. Some parts of my land when I moved here remained bare of even weeds for years. Not a single weed would grow in those places.