Question
A landscaping company planted 6 jaquemonti birch in my yard at the end of May. Two of them recently began developing darkish brown leaf spots in the center. They are getting plenty of water. On one of the leaves I found very tiny black insects. I did not find insects on any of the other leaves. What could the problem be and what should I do about it. I picked the infected leaves off that I could reach. I also collected the insects.
Answer(s)
From your description there may be two different things happening. The first possibility is that this particular type of tree is not heat tolerant and the leaves may be scorched because of our hot and dry weather conditions. This problem usually shows up in July and August with newly transplanted trees being the most susceptible because they have yet to develop extensive root systems. I have included a link below that has more information on leaf scorch.
The second possibility is that what you are seeing is a fungal disease. Fungal diseases usually start out as dark brown to black spots. These spots will spread and eventually grow together and in severe cases the leaves may die and fall off. When we have long periods of cool wet weather, like we did this spring, fungal diseases can be more problematic. If it is a fungal disease the good news is that now that we are having much hotter and dryer weather you should see a significant decrease in the spread of this problem. Below is a link with more information on a common fungal disease in our area. If it is fungal, some things you can do to help your tree out are to make sure to pick up and discard any of the leaves that fall off of this tree. This will help reduce the spread of the fungus. When watering the tree try to avoid getting water on the leaves. If the tree is watered by sprinklers make sure to run them early enough in the day so the leaves will be dry before nightfall. Below is a link with more information on watering trees. You can also apply a protective fungicide spray at bud break and to the newly emerging foliage next spring.
http://utahpests.usu.edu/plantdiseases/htm/ornamental/leafscorch
http://utahpests.usu.edu/PLANTDISEASES/htm/ornamental/anthracnose
http://extension.usu.edu/files/publications/publication/HG-523.pdf
If neither of these look like what you are seeing on your trees please bring a sample into our office at 2001 S. State Street #S1200 for help with diagnosis.
Other Questions In This Topic
- I have varmits that are ruining my lawn during the winter (under snow). They make trails and destroy the lawn about 4 inches wide. I can find no holes only the trails and dead grass flipped to the side of the trails. Any ideas? We are going crazy trying to figure this out. We have never had this problem until last year.
- We moved into our 2-story home in Lehi 1 year ago. The tree out front (which I planned to have my husband cut donw) has doubled in height since then. I don't know what kind of tree it is...medium size, darkish leaves. How do we (and when should we) cut it down to prevent it from sending up suckers?
- I've just moved here from Maryland and I'm starting to landscape our yard. I've noticed that none of my neighbors use mulch in their flower beds. Why is that? I thought mulch helped to keep the soil moist as well as keep out the weeds. Plus you can till it back into the soil in the fall for aeration.
- When and how do I harvest my butternut and buttercup squash?
- My mugo pine is turning an orange color and the needles are dropping. What caused this and can it be saved?
- Do you have a list of good varieties of produce producing plants to grow in this area? I am looking to plant fruit trees this fall and start a garden next year.
- We currently have an elm tree in our front yard. It has been diagnosed with slime flux. We would like to plant another tree next to it,seeing as they said the stump was so big that they would just leave it. Will this cause a problem for any other trees? We want another large shade tree. Will it get the slime flux too if we plant it near it?
- i was baking a chicken casserole last night. the power went out after about 30 minutes of baking. i put it in the fridge. then, i cooked it for 1 and 1/2 hours more when the power came back on 3 hours later. i put it back in the frige. is it safe to eat tonight?