I'm Stubbed.

I've seen a rash of poorly pruned trees lately, and I think the picture below enforces why we should prune trees at the branch collar.  See the lower part of the branch forming callus tissue. This area is the remaining natural branch collar.

The rest of the cut is well outside of the collar, forming a stub.  You see how the tree has been unable to form reaction growth around this area.  This now leaves an entrance for pathogens, and may cause harm to the tree.  It also doesn't look very good.

Sometimes it isn't easy to get that final cut right, but its well worth your time.  Happy pruning out there.

Native Ash Trees: Oh No

I was at the ANSI IPM summit this week, and had the privilege to hear several industry leaders talk about the state of IPM. Dr. Mike Raupp from the University of Maryland was one of the speakers.  Dr. Raupp informed us the US stands to lose over 8 billion ash trees to emerald ash borer.

While this is tragic unto itself, something I hadn't thought of before was the effect on other species of plants and animals that have a symbiotic relationship with ash trees in the wild.  Untold numbers of animals use ash trees as primary food sources and shelter. In a greater view there are untold more animals that rely on the 1st bunch for food, seed dispersal, germination, etc.

So, what to do for these poor unfortunate creatures?  The Manchurian ash (Fraxinus mandshurica) has a natural resistance to emerald ash borer, and is similar to our native ashes.  Would it be possible to begin replanting our imperiled ash forests with Manchurian ash? If it is, could we save numerous species of plants and animals from possible extinction, assuming this Asian ash species would be a suitable substitute for our native ash?  Or would this exotic ash fall victim to a native pest our endemic ash has long since built resistance to?

These are interesting questions, and play a role in the future of our landscapes, forestry, and conservation arboriculture.

Manchurian ash, could you tell the difference.

The Scourge of Imidicloprid

If you're like me, then while your wife is looking at power tools at Home Depot, Lowes, or wherever, you are looking at the active ingredients on pesticides in the garden aisle.  Which means you have probably noticed that many general purpose over the counter insecticides are now imidacloporid based.

As an industry, we have relied on imidacloprid, Merit in its most popular form, for more than a decade.  Applied properly it is a great product.  It is in the neonicotinoid family of chemicals, and its mode of action is kind of neat.  The chemical interferes with an insects nervous system which results in death. Imidacloprid can be applied as a foliar spray, soil application, or directly injected into the trunk.  It is nontoxic to mammals, has a long residual, and can be quite effective.

However there are some things we need to consider when using this pesticide.  Studies have shown that with repeated use the molecule can make its way into the flowers of plants.  For trees and shrubs that are not wind pollinated this exposes pollinators to the product, and may lead to civilian casualties in the war against plant pests.

The other issue is pest resistance to imidacloprid.  In some areas imidacloprid has been so heavily used that it is no longer effective against targeted pests.  With imidaclolprid now being readily available to the public at large, and continued reliance on the chemical in many professional PHC programs, we may only assume that this pest tolerance will grow.

There are few 'silver bullets' in pest management.  Product/chemical diversity is an important part of an IPM program.  Imidacloprid may still be part of your chemical arsenal  but pest monitoring and investigating different products for use on target pests should be on the forefront.

The molecule