Question From: Harleysville, Pennsylvania, United States
Q: Hi Nancy...we have a 15 year old river birch that for the last 3 years 1/2 the leaves have been turning yellow and dropping off by the end of June. The leaves come out beautifully in spring. We have sprayed it on recommendations from the local nursery. This seems to begin when we have very hot spell. Thanks, Marilyn
A: Your tree is suffering from lack of iron and water stress. River birch get stressed in hot dry weather, Water it twice a week when things heat up. Milorganite contains 4 percent iron and is an organic fertilizer that also helps feed the soil. Spread it under the canopy of the tree at a rate of 1 pound per inch of the trunk diameter at breast height. If it is multi-stemmed measure each trunk - add the total and divide by the number of trunks. Use the Milorganite in spring and late fall. Mulching the tree with 3 inches of wood chips would also be helpful, Best And Happy Yardening, Nancy
