Is this heat stress or something else on the new apple trees?


#1

I planted some beautiful bareroot and bench grafted Apple and pear trees this spring from 39th Parallel Nursery. Mike grows great stuff!

I am not having a lot of success with anything I planted this spring though. I don’t know if it’s the weather or something I have or haven’t done, but my bareroot apples and benchgrafted pears have not done well since leafing out. Since our temps got really hot really fast, I attributed it to heat stress. They are mulched and haven’t gotten dry, I check them daily, only missed a day or two since planting.

They haven’t put out any new growth, and the leaves started curling as temps got hot. They are curled up tight. In the last couple days, the leaves on Shinko pear, Cripp’s Pink and Hewe’s Crab apples have turned brown and dropped.

I planted them April 17 & 19th. I sprayed 5-22 with Immunox/General Bonnie Fruit Tree/Bt. On 5-30 sprayed with Immunox/Captan/Bt. I didn’t write the date down, but they got a shot of spinosad after a rain. I had a few green caterpillar type guys eating new leaves, so the Bt and spinosad were to take care of those. I saw some leaf spots but nothing serious and thought the fungicide would take care of it. I don’t know what spider mite damage looks like, but have checked leaves with a magnifying glass and haven’t seen any sign of small mites or eggs. There is some cobwebby stuff on some of the leaves but I don’t see a source, unless it is from actual spiders, but looks differ not to me. I found a few spiders hanging out in the curled leaves.
I will post some pictures so you can see their general state at this point. Any help would be appreciated! I don’t know what I have missed here, but I haven’t done something right! I apologize there are several photos that follow…

The leaves on most of the trees are small, not bigger than the size of a quarter.

Not much left but some brown leaves on the Cripp’s Pink, found webs inside of two curled leaves.


#2

Windy there as well? Many of those leaves do look a bit heat-blasted, and a stiff wind would just dry them out faster.


#3

Looks like u get super hot dry winds


#4

I wonder how much of those leave damage was caused by Captan burn. Captan is known to burn leaves at certain condition.

Captan and Immunox are both fungicide. You mentioned that you sprayed both plus BT at the same time. That’s made me wonder how much those young leaves could handle.

@alan, @Olpea and those who know a lot about chemicals, could be able to give you some answers.


#5

Yep, it has been very hot and windy.


#6

Mamuang, I didn’t know Captan could cause leaf burn… I looked up the weather those days and we had mid 80s for temps, low winds both days. I don’t know if that makes a difference?


#7

Captan burn causes brown spotting that sometimes leads to the yellowing of leaves and their dropping. A certain amount of it is very common, but it usually has no important affect on trees- only removing a small percentage of leaves. That doesn’t look like captan burn but I’m surprised dry, hot wind would be that destructive if the trees had adequate water- but I’ve never grown fruit in an area with such challenging conditions.

I’ve seen a lot of Captan burn here this year because early spring was so cool and wet that the leaves were still quite tender at petal fall. Dry weather hardens the leaves and leaves them much less susceptible.

Were the trees fully dormant when planted? They look like they might be stressed due to an inadequate functioning root system. Sometimes when I heal in trees and transplant them long after they have begun growth they suffer a bit like yours. Seems like your planting date may have been a bit late for KS. The surviving trees might benefit from some southside shade.


#8

Here’s a couple pics of captan burn (figure 1, 2, 3).

It doesn’t look to me like captan burn. I don’t think it’s the hot wind either. It has been hot here in KS, but I’ve never seen heat do things like that to newly planted apple trees. I was thinning apples yesterday and walked by some new apple trees and they don’t look like that.

Normally, mid April might be a tad late for planting for our springs, but as you know we had a really late spring this year so I don’t think that’s the issue either.

I think there is a good possibility it could be some root issue, but you mention you have check the soil daily. But, just to double check all the bases, have you taken a small hand spade and dug down beside the tree (say, at the edge of the wire cage) to a depth of where the roots would be? From the pic, the ground looks like it could be dry, and as you know, it’s been fairly dry here this year. Grass that close to the tree will suck up a lot of moisture. I lost some newly planted apple trees in 2012 when it was so hot and dry. But the ground was very very dry.

If the ground is still moist down where the roots are, then another possibility I can think of is perhaps some herbicide left in your sprayer? A very small amount of glyphosate (Round Up) can be very slow acting and would cause very wimpy growth/slow death. That’s probably unlikely though, because it looks like you have perhaps another older tree in the background in one of the pics, which was probably sprayed with the same sprayer?

Lastly, the new trees look really tall. I can see in one pic you tied off one side of a tree. If the trees are catching a lot of wind and whipping a lot, it can wallow out a hole and the roots won’t have a chance to settle in. When you scrape back the mulch around the trunk, are you seeing any evidence of wallowing out?

If it’s not one of those three things, then I don’t know what is causing your trees to stall and die, but I don’t think it’s the heat.


#9

Go stand in front of a commercial, forced air, furnace add 30 mph sustained winds for a few days … Welcome to the Great Plains!!:grinning: Every region has their challenges, that would be one of ours. On the plus side most of the fungal diseases are minor at best here.


#10

@alan, @Olpea, @TurkeyCreekTrees,
Thanks for your input and expertise guys.
I did plant the trees later than I wanted to… After I picked them up from the nursery I kept them in our cool basement, in the dark, for 10days before I planted them. I waited to plant due to snow shortly after I got them, and then because we were having crazy winds that whole week, sustained at 30+ mph most days, gusts in the upper 40mph range. Some nights it never calmed down at all, it just blew and blew. Anyway, I was worried about them being able to handle the wind before roots were established. I don’t stake trees as a general rule, as I have read that can do more harm than good and trees need to “learn” to bend with these constant winds. Perhaps I was wrong on this too? That one tree in the pic I did tie because it had a bend I didn’t like and wanted to try straighten out if possible while young.
When I planted the trees I remember the buds were definitely swelling on most and on one leaves were beginning to emerge but can’t remeber which one that was.

Ok, I am back from checking trees. A little background- The trees are planted in slightly raised mounds of native soil that are 6”-8” high and 3’-4’ diameter.
I have been weeding the mounds and trimming around the cages to keep grass down. Not perfect but I try keep up with it.
Soil moisture is still good around the trees under the mulch as well as at the outer edges of the mulch/cages when I dug with my hand spade.
Even so I will be watering tomorrow since we don’t have any substantial chances of rain this week and I don’t want them to get dry.
I do see some signs of what I think you refer to as wallowing though. Some of the trunks feel loose when I grab them and I can see maybe 1/8” gap between trunk and soil on a few.
I took extra care in planting these, which I thought was a good thing. I was careful to not bunch up the roots, but spread them as I thought they had been growing in the nursery, filling with soil kind of in layers to avoid air pockets or gaps. Watered in well, etc. I didn’t pack the soil down really hard, but watered, let the soil settle, watered, settled, etc. With this clay soil, if packed too hard, it dries to something similar to concrete.
Checking my record of rainfall, I am now thinking they may have gotten dry at some point mid May and I missed it. Life got pretty busy for a week or so and rains were sparse and spotty. I make it a routine to walk through and check trees every morning, but I know I missed some.
@Olpea, I looked at the link you posted. I think maybe I am seeing similar spotting and leaf edge burn on 3 apple trees I got from Vaughn nursery, planted earlier in March. I will also post a picture or two of some grafts, some leaf spotting I can’t identify. All these trees got the same spray treatment, with exception of the grafts, which I excluded from the first spray on 5-22. I apologize for picture quality, it’s very windy again today!!


#11

They weren’t planted too late. If the wallowing theory isn’t the answer, another possibility is the trees drowned from kindness and clay. Here, the quickest way to kill a tree is to plant it in clay mud. A drowning tree looks pretty much like your photos. Clay needs to be fairly dry before it can be worked and planted. It is so much easier to do diagnosis on-site than via photos.

The wind helps trees develop taper when they aren’t staked and this is very useful for large ornamental trees, however fruit trees in windy areas often benefit by being planted with deeply set, conduit piping where they remain attached often for their entire lives- although I like to cut them away to make pruning easier by the time they are fully mature. Of course, I haven’t done so in KS, but we do get occasional hurricanes coming through- all it takes is one weather event like that to test trees. On apple trees, at least, I’ve noticed no particular loss of taper by being staked for years.


#12

@alan, thanks so much for sharing your knowledge… After I reading your reply, I’ve been thinking on what you said, going over possibilities, looking at my trees… ugh. It’s just confusing.
I could benefit from some on-site help from an expert, for sure. :wink:
The soil wasn’t wet when I planted, and while I watered them in well, it was not overly much in my estimation. I didn’t soak them and leave them in a soggy mess, I understand and agree that is a very bad thing to do in this clay. But, something is obviously wrong. I still have so much to learn. Let me know if you think of anything i can do for them at this point, other than get them some south side shade that you mentioned earlier. I have planted a lot of trees over the years, not saying i have done it well every time, but I haven’t had this happen before.