Pine trees browning and dying in sequence?
Good evening! We have a series of pine trees at the road line near our property, and they've begun dying off. At first we thought one or two had just died during the soggy winter, but it appears that the symptoms - brown leaves, loss of needles, and withered pinecones - are spreading in sequence to other trees in the line that rings the end of the property. Web searches suggest a number of possible causes - too much water, too little water, some kind of fungus - but we'd love to get some input on what we should do next to preserve the remaining healthy trees. Thanks for your time!
These Leylands have bagworms. The old bags from last year are still hanging on the trees. It is too late to pull off the bags, which were full of eggs. The eggs have already hatched and your Leylands probably have very small bagworms feeding on the trees now. Here is how to control them now to you don't lose more trees: http://extension.umd.edu/hgic/bagworms-trees-and-shrubs
Bagworms slowly eat the foliage of trees and can certainly kill them.
Thank you very much for your help!
Have a great holiday!