Fruit Grower’s Journal

Rain and clouds have dominated over the past two weeks.  There have been a couple of breaks but those breaks have been rare and short-lived.

How are our fruit crops surviving all this lowery weather?

Surprisingly well!  We have a nice crop of apples, one that will size up well given the ample amounts of water available.  And our strawberry crop, picked between showers, is the best I have ever seen.  A few blueberries and raspberries are ready and sweet cherries, just hitting their peak, are simply delectable.

One interesting pest of apple I ran into last week was a Prionus rootborer.  A grower was losing a few 4 or 5 year old trees.  These trees had leafed out, but were not growing and leaves were small and yellow.  It seemed likely the problem was a root issue so we pulled up a couple of trees to see what was going on.  The trees were almost completely eaten off just a few inches below the ground and a critter was happily feasting on main stem of each just below ground.  These guys get big – this one was nearly 3 inches long and appeared to be well-fed.

This borer measured almost 3 inches in length and had killed a 5 year old apple tree. Photo: W.Lord

This is the bottom of the trunk just below ground. Check out the tunnel this one is making as it eats its way through the wood. Photo: W.Lord

How do we protect our young trees from this type of attack?

First, keep the area around trunks of young trees free of tall grasses and weeds.  Keeping vegetation short eliminates the cover the adults prefer for egg laying and allows natural predators like downy woodpeckers access to a meal.

Consider painting trunks of smooth barked young trees in particular with white latex paint. Repaint each year to provide a deterrent to egg laying adults.  This will also protect these young trees from winter injury caused by temperature fluctuations on clear, cold days in winter.

Use a barrier to keep adults away from trunks.  Aluminum screen fabric works well.  Wrap the trunk from the ground up to the first branch, tying off the top with twine and covering the bottom with soil.  Barriers should be applied by early May and removed in September.

Bill Lord, June 28, 2009