I have a row of Norway Spruce, 30-40 in number, planted around perimeter of...
I have a row of Norway Spruce, 30-40 in number, planted around perimeter of yard. 35-40 years old. Most trees look very healthy. Several have died in the last 5 years, start dying from the top down from the top down. No signs of frass, insects lightning strike, etc. Any ideas?
Are the trees that are browning all in the same area or scattered along the perimeter?
Does their placement have any bearing on whether they are more likely to be sitting in wet soil, or conversely be the first affected by drought?
Bark beetles can cause dieback from the top down. Are the needles there and dead or are the branches bare? Gypsy moth is another idea. They will eat spruce.
Any root interruptions by equipment or traffic?
It's a tough one.
If the trees are important to you, your best bet is to get an on-site evaluation by a certified arborist, who can take all factors into account. You can search for an arborist certified by the International Society of Arboriculture at www.treesaregood.org.