My new location is surrounded with pine trees. I worry about my new garden and need some words of assuranceš. Googling doesnāt help much, as they always discuss extreme situation, like planting UNDER pine, in itās shade,. My garden will be not in the shade of the pines, but I am sure the pine roots will eventually find my beds. Here is the things I am already doing: making raised beds with a lot of organics matter, adding lime to correct PH, prepared shredded leaves for mulching to retain water, planning to remove needles if blown to the beds by wind in fall, dig the beds every year to remove roots of the trees if found. With all that said , do my veggie have a chance? What about apple trees?
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My daffodils do well under the pine tree. Curious to see what other say about fruits and veggies.
I would test the soil before adding lime. In my case the pH of the ground is closer to ideal under the pines compared to the rest of the yard. The pH is higher in the yard. I do have some plants under the pines and it seems the ground there dries out much quicker. I think this is a combination of the pineās root taking more water and the fact the roots help aerate my heavy soil.
My pines are large trees and were planted thirty five years ago. Directly under the pines I have trouble digging since you hit lots of roots with the spade. But if you move out from under the trees itās not much of a problem. I donāt think roots will be a major problem if your raised beds are not under the pines. Also pine needles make good mulch.
The vegetables and apple trees should be fine.
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Pine trees have no affect on pH, unless needles are carried away, in which case, pH is lowered more slowly than when deciduous tree leaves are removedā¦ deciduous leaves contain significantly more calcium. So the needles add less calcium than deciduous leaves when used as mulch, but they donāt, somehow, remove C from the soil.
Pine trees, like all trees, compete for water and nutrients, and if you break any big treeās roots to plant young trees, those roots will send out vigorous feeder roots at the exact point they are cut, just like a stub cut on a branch excites vigorous vegetative growth within a few inches of the cut. The loosening of soil beyond the cut exasperates the problem, even while helping the new treeās roots grow- the advantage provided the established tree overwhelms the advantage to the new one. This can make establishment of new trees difficult. Sometimes a trench or otherwise cutting into the soil well beyond the roots of the new tree to sever competing roots is necessary to create conditions for rapid establishment but once new trees are established this usually is no big problemā¦ but it all depends on a range of factors such as soil depth and the amount of water made available by precip or irrigation, or the available water held by the soil type.
As far as any chemical warfare going on, I am unaware of any allelopathy in play with conifers, although Iām suspicious of our native red cedars here. White pines have another tactic, apparently. Their needles create a hydrophobic compost that keeps water from seeds that fall on it. I suppose the pine root systems spread beyond this affect to lap up the runoff.
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Somebody already mentioned a soil test.
Iād suggest that the pines create a lot of protection from the breezes, and probably even from frosts. So, some things may do better than normal near the pines (and some not of course).
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Explain that a bit using some proof: āpine trees have no affect on pHā.
The needles dropping certainly do affect the pH as they decompose.
Why should they, what chemistry would make it possible? You can look it up, but I had a client 25 years ago with big white pines that were allowed to sit in their own mulch for decades. I decided to test it out and did pH tests under the trees and a good distance away in the same soil without the influence of the trees. The pH was identical.
There is very little specific research on the affects of pine trees themselves on pH but that is probably because it is understood that plants in general donāt have the ability to change the pH of the soil one way or the other. Otherwise maybe blueberries would be able to grow in any soil and just change the pH to their needs.
The following is form this. Pine Trees Love Acidic Soil ā But Donāt Make The Ground Acidic
You may have heard before that pine trees make the surrounding ground more acidic. According to the University of New Hampshire**, this is a myth. Pine trees do not create acidic soil.**
While it is true that pine needles themselves are acidic once they have fallen off the tree, they will not make your soil more acidic. As the needles decompose, they slowly become neutral. (They make good mulch if youāre looking to repurpose the gift your pine tree keeps bestowing upon your yard.)
A study published in Hort Technology showed that if a pine tree is used as a substrate (ground up into pieces to serve as a makeshift soil), it would still need additional fertilizer to be acidic enough to sustain plant life.
This is a classic case of ācorrelation does not equal causationā. Pine trees donāt cause the soil to become acidic. They grow well where they do because the soil is already acidic.
Pine Trees Love Acidic Soil ā But Donāt Make The Ground Acidic
You may have heard before that pine trees make the surrounding ground more acidic. According to the University of New Hampshire**, this is a myth. Pine trees do not create acidic soil.**
While it is true that pine needles themselves are acidic once they have fallen off the tree, they will not make your soil more acidic. As the needles decompose, they slowly become neutral. (They make good mulch if youāre looking to repurpose the gift your pine tree keeps bestowing upon your yard.)
A study published in Hort Technology showed that if a pine tree is used as a substrate (ground up into pieces to serve as a makeshift soil), it would still need additional fertilizer to be acidic enough to sustain plant life.
This is a classic case of ācorrelation does not equal causationā. Pine trees donāt cause the soil to become acidic. They grow well where they do because the soil is already acidic.
https://extension.unh.edu/blog/2019/10/do-pine-trees-pine-needles-make-soil-more-acidic
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Letās see if I can get this list to up-load. Of 33 species of trees and the pH of the leaves of each as they drop to the forest floor:
I find from many years tending soils in lots of places that this list isnāt off much.
Maybe you can learn something here.
But the question is, can pine needles appreciably lower pH of soil. I already said that deciduous trees tend to contain more calcium, so maybe over many years they can slightly raise the pH of soil but for all practical purposes pine needles are not a factor in reducing soil pH.
Searching further I did find a Polish American āstudyā where they tested soil under pine trees after a 30 year interval and that the pH had dropped there a small amount, but one test like this is no more convincing than the test I made that showed the opposite, and it would require a lot more research to get a definitive answer as to whether over time pine trees can measurably acidify soil. However, I failed to bring up the study and only read an article that referred to it.
All trees take up calcium so there is bound to be a slight acidification created as trees grow, right? I would think that the more calcium they pull up the more theyād acidify the soil so pine trees should have less affect than deciduous trees.
Once again, the issue is mute in terms of practical consequences, IMO.
It might be moot in your mind.
Anybody can study the forest floor on the same hillside under pine trees vs under tulip poplar trees or elm trees and be educated by things they observe.
So have you done that?. My comparison was between sod and soil blanketed with white pine needles for at least 3 decades. Lots of studies have been done on the affects of pine needle mulch and all Iāve seen have shown no appreciable affect on pH.
You believe all the hype of the thousands of stories on climateā¦so you similarly believe a half dozen stories that leaves donāt affect the pH?
āHave I done that?ā
Havenāt your read enough of my posts to realize I can trapse through the forest and most people cannot spot a tree I cannot name. Of course I have studied the forest floor!
You donāt look for mushrooms or truffles or mountain tea underneath all the trees in the forestā¦just under the right ones.
If a tulip tree and a virginia pine are 50 feet apart on the same parcel of land, doesnāt mean youāll find the same smaller plants under both species.
So, again, pick your studies and believe the ones of your choosing.
The list I posted is correctā¦because it approximates the same thing Iād tell you as I trapse through the forest and look at the leaves.
Iāve drawn my living from the soil for over 50 years and have lots of strong opinions based on anecdotes but when providing advice to others it is nice to know there are controlled studies that support my experience.
You havenāt provided much to support your opinion besides a list of the pH of various species of leaves while others have compared the results of using various mulches on the pH of soils over time. Itās not exactly the kind of research that is propelled by hype or profit motive, although they are starting to sell bales of pine straw for mulch, but these studies preceded this and I donāt think the industry is very large.
I have three raised beds (~ 10") on the south side of a row of pine trees. They are not shaded by the pines but it is highly likely that the pines roots to some extent grow under the beds. I have not had any particular trouble. I have grown a lot of squash-types, peppers and tomatoes there. For one season I converted 1 bed into a nursery for apple bench grafts. Until I read your post I hadnāt considered that the tree roots might be an issue.
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