Hello,

Could you please attach a picture of the whole tree, one of the insects( on a plain piece of paper if possible), and one of 5 or 6 leaves on a plain piece of paper- turn some leaves face up and some face down.

With that information we may be able to narrow it down.

Here are picture guides of common birch tree issues. You may have birch leaf miners, or rust. The small  insects may be aphids.

https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/birch/leavesspots.html

http://www.uky.edu/Ag/Entomology/treepestguide/birch.html

In any case, what you can do to help your trees is give additional water so that soil about 10-12 inches down is moist. Birches need water and, if it has been dry in your area, a soaker hose or a sprinkler set very low so it dribbles out water, will help the tree. Well watered trees can fight off most insect attacks, and will sprout new leaves. I will watch for your photos.

Hello Tom,

Thanks for the pictures. In future you can call the hotline number listed below for help too, they can walk you through how to attach pictures here)

The insects are barklice nymphs, and don’t harm the tree. They are considered beneficial insects. Here is more from Extension-

“You may wonder why barklice are being included as beneficial insects. As scavengers, they perform a valuable function in consuming excess accumulations of fungi, algae, dead bark and other materials that occur on tree trunks and large limbs�in effect, they function as �Bark Maids� to help clean the bark of undesirable inhabitants.

Barklice do not eat leaves or the bark of the tree, nor do they damage the tree by boring into the bark. Although they may be viewed as unsightly, they are short-lived and harmless.

No control measures are recommended for these insects. Treatment is not recommended as the barklice are providing a beneficial service by helping Mother Nature to keep the bark clean and tidy!”

More on the insects  here- https://www.canr.msu.edu/news/tree_cattle_roaming_the_range

The first Picture  I was able to lighten enough to see some details. It shows quite a bit of other plant materials around the birch trees. Birches  like plenty of water so, be sure these trees are well watered during dry times like we have had this year, since a light watering with a sprinkler will not give them enough. The other plants around the tree will take up the water first. To check,dig a small hole 10 to 12 inches deep in the root zone after watering to verified water got deep enough for the tree roots.   

The picture of the leaves came out very blurry so it is difficult to see the spots clearly. It looks like some birch leafminer( tan irregular spots), and anthracnose(dark circular spots). I am attaching a link which has clear pictures of these conditions, so please take a look.  It has further links to control options. https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/birch/leavesspots.html

 I hope this is helpful and, if you have more questions, you can either update this question thread or  give the toll-free number for the Garden Hotline a call.

Regards, Laura