Aphid tree investation
A number of trees in our neighborhood appear to have an aphid investigation . A tree company confirmed this. The trees leaves turned yellow, curled and dropped early this year. The black aphids were seen on most of the leaves, along with white aphid poop( ?) and yellow " honeydew " substance as well. I have discussed this situation with a rep from the county tree service, who says the county will not treat the investation, but will replace the tree if it dies ( and if there is funding available). All of my research thus far has determined that spraining the trees is the best treatment option. Due to the fact theses are 25 year old Maple trees, and are quite tall, and because so many in the neighborhood are affected this is highly impractical. Are there other options, possibly systemic for treating this ?
We do not recommend spraying trees for aphids. Aphids are usually controlled by early summer as a result of the actions of beneficial insect predators and parasites.
Use of insecticides is impractical and not good for the environment. Their use can eliminate beneficial insects (like ladybugs, that eat large numbers of aphids) for a long time.
This years weather made for a banner year for their numbers. Hopefully next season will not be as bad.
The white things that you saw on the leaves were shed skins, not poop.
Here is our page on aphids: http://extension.umd.edu/hgic/aphids-trees-and-shrubs
Note that using high nitrogen fertilizers (even on grass beneath) can encourage lush growth that attracts aphids.
Honeydew, the sticky dripping, can also be from scales insects as well.