July 11, 2012
Some trees in Iowa have been losing leaves over the last few weeks. Foliar diseases, dry weather, and Japanese beetle defoliation are the primary reasons for the leaf drop.
Foliar diseases, such as apple scab on crabapples, cause spotting of the foliage and premature leaf drop. The premature leaf drop weakens crabapples, but does not kill the trees. The damage is mainly aesthetic. Raking and destroying the fallen leaves may reduce the severity of the disease next year.
It seems a bit early this year (as everything is), but wasps are becoming very noticeable. We group wasps into 2 major categories: social wasps and solitary wasps.
The zebra swallowtail butterfly (Eurytides marcellus) is one of six species of swallowtails found in Iowa. While you are much more likely to find them in the southeastern part of the