Trees/Black and white bumps on Mimosa Tree
I have a Mimosa Tree in my yard. We are located on the eastern shore. Soil is sandy and clay. Don't know the PH or any other conditions. I noticed these bumps the other day. I have attached pictures of them, as I can't describe them very well. I have had the tree for about 5 years, and this has happened once before. I just scraped them off and did not have any more problems till this year. when I scrap them off, they are filled with a sawdust like powder, and some have a viscous yellow substance in them. They don't seem to be boring into the tree, and the tree is currently blooming as it should this time of the year. Any help on what to use to get rid of them, or even if I don't need to worry about them. Thanks for your help.
These are scale insects. They live in the turtle like shell and suck the plant juices from the tree. They usually secrete a substance called honeydew which is high in sugar content and sticky. The sticky sweet honeydew will attract insect and wasps. The easy thing to do is treat the tree with an insecticide called Bayer Advanced Tree and Shrub Insect Control. This is applied to the soil around the tree and the roots will transport the insecticide to the leaves and branches and when the scale insect sucks the plant juices they are killed. This will prevent infestations for the growing season. Here is a web link to this product. Check with your local garden type store for this product. http://www.bayeradvanced.com/tree-shrub-care/products/12-month-tree-shrub-protec