What is causing the annual mid-late summer folding of leaves on multiple trees in our yard? Miss Kim lilac bushes, Tina crab, black choke berry. All leaves on tree/bush are folded inward along the middle vein. Leaves at the top of the bush also have brown spots and edges whereas lower leaves look perfectly healthy and bright green - just folded inward along middle vein. Recent UM soil test report for soil around three Black Hills Spruce trees in yard indicates very high phosphorus levels and a relatively high pH of 7.8. Soil is medium texture and organic content is 6.8%. Recommendation was to add 0.07 lbs N to 100 sf. Not sure how similar soil around these trees is but I would guess very similar as the landscaping was done at the same time using similar soil. The bushes and tree look great in the spring, but this folding of leaves occurs every July/August. Thanks for any help you can provide! Pic 1: Miss Kim Pic 2: Choke berry Pic 3: Tina crab
Carver County Minnesota
The trees/shrubs in the photos appear to be fairly healthy for this time of the year. The various spots could be fungus. With all of our rain many plants have it. I would suggest taking up and disposing on any debris this fall rather than composting. I would expect these to come back healthy in the spring. If you notice additional symptoms such as dead branches, cracks in the trunks, leaf decline or drop I would recommend having an arborist from a local tree care company look at them.
Thank you for your input.