Answering Your Tree Questions

By Dr. Francis Gouin

Vertical Mulching and Tree Roots

Q   I enjoy your articles. Recently you’ve written about trees & Bloom.
   I have two chestnut oaks that now have slime flux. Do you think your method would help these trees? I have called forestry schools, and they tell me I can’t do anything. Commercial tree companies want to sell me a fertilizing service for $1,000 with no guarantee.
   Would drilling at three feet cut through and damage the roots? I have about 20 of these oaks and all have shown some stress the last few years. I wouldn’t want to hurt their roots.
   Do they sell Bloom in the Annapolis area? Or is there some substitute?

–Dave Bastian

A Making the tree healthy is the best treatment for curing slime flux. Vertical mulching with Bloom ASAP will stimulate those chestnut oaks to generate new growth, which will result in compartmentalizing the region in the trunks that is generating the slime flux.
   I vertical mulched using compost on my own cherry bark oak tree here in Deale 25 years ago when we moved here, and within two years the slime flux stopped. I drilled six-inch diameter holes. Don’t worry about damaging roots. If you hit the roots with the auger, the tree will generate new roots from the damaged area. When a tree is dug, balled and burlapped, the tree loses 80 percent of its roots, and it recovers.
   I have vertically mulched my 200-year-old cherry bark oak five times, and it is healthier than ever.
   Bloom is sold at Homestead Gardens in Davidsonville.

Girdling Ivy Kills Trees

Q   I enjoyed your vertical mulching article in Bay Weekly. I have two large silver maples and another mature tree. Vines have almost completely covered them, and I wanted to know if this is harmful and should I remove it. I imagine it would damage the bark to just rip the vines off after they’ve gotten so attached. And the deep vines up in the trees do provide habitat for birds and squirrels. But if it’s killing the tree, then I guess I need to take action.

–Rich Kavanagh, Deale

A The silver maple is a short-lived tree. Yes, I have seen over the years where English ivy has killed trees. This will occur if the vines completely circle the trunk and you can see the bark of the tree growing over the vine. It kills the tree by girdling. If the vines are mostly growing straight up the tree, like many do, it is not a problem. From the looks of the top growth visible in the picture you sent, it appears that the new growth is sparse, which means that the vines appear to be girdling the trunk.

Replacing a Silver Maple

Q   We have sadly watched a large silver maple die over the past few years. It was probably about 50 years old and the source of a plague of box elder bugs. We are having it removed soon and need to know a good replacement. Also, will we have to wait to see if there is any disease or bugs in the soil that could infest a new tree?
   Do you have any suggestions for a quick-growing shade tree? We are thinking honey locust or dogwood. Our home is in Upper Marlboro.
   We really enjoy your column. Thank you for your advice.

–Leda Kress, Upper Marlboro

A Most fast-growing trees such as silver maple have short lives. However, the Shade Master honey locust is a fast-growing cultivar that has a relatively long lifespan.
   The box elder bug only feeds on female box elder maple trees. We have lots of box elder maples growing in this region. I doubt very much if the bug caused the death of your tree. Silver maple trees are prone to fusarium wilt, which may have been the problem. Since it has had a slow death, I strongly suspect that your tree was infected and you need not worry that it will affect the Shade Master locust.

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