Saturday, June 30, 2012

Bug Wars

In this post I am giving an update on what we have been doing in the garden in general, and the bug wars we have been fighting in particular.

It has been hotter and dryer than usual for our area so far this summer.  Another thing we have noticed is that there are almost no beneficial insects around to speak of, a single might be spotted here or there, but that is all.  Our Brassicaceaes have been plagued with cabbage white larvae, but even more damaging are the aphids that cause the plant leaves to shrivel up.

This year to combat the squash vine borer we discussed in an earlier posting, we put some aluminum foil around the base of our zucchini plants, and as an extra measure we put row covers over the plants as well.  It was just in time too as we saw the borer adult trying to lay eggs on the plants, right at the base where it will do the most damage!  The idea with the row covers is to keep the adults, which are actually a day flying black and red moth away from the plants.  This works until the flowers come out, then we need to remove the row covers to allow them to get pollinated.  The hope is that the borer adults will not be around later in the year. Although last year I recall seeing some adults much later than they were supposed to be out, probably due to our cold, wet spring.
Covered Zucchini to combat squash vine borer

This year we are finding a new menace, similar to the squash vine borer.  Our raspberries are being hit with the raspberry cane borer!

Excerpt on Raspberry cane borer from University of New Hampshire Cooperative Extension (

The adult cane borer is a slender, black beetle with long, black antennae, black head and yellow prothorax. Adults are about one half an inch long. The larvae are legless, light-colored borers found within the stem. Fully grown larvae are about 3/4 inch long.

Life Cycle
This insect has a two-year life cycle. Adults emerge beginning in June and females lay eggs in the pith of new raspberry growth, about six inches from the tip of the cane. The female beetle then makes two rows of punctures around the cane, one just above and one just below the egg-laying point. This causes the tip of the new cane to wilt. The egg hatches in early July and the larva burrows slowly down the cane, passing the first winter within and inch or two of the girdle. During the second year the larva burrows down to the crown and passes the second winter at or below ground level. It completes its development the following spring and pupates in the soil.

Chemicals are not necessary to control this pest. Cut girdled canes an inch or so below the girdle and burn them soon after cane borer damage appears. Attacked canes wilt, making the damage easy to spot. Eliminating wild raspberries nearby will reduce damage. Since the life cycle requires two years to complete, regular pruning usually keeps the population in check.

If caught early I found that I can easily snap the cane at the lower ring and split the cane apart to find and squish the larva.
Wilted Raspberry Tip...  Check for cane borer.
Close up of cane borer damage, girdled cane markings.

On another subject, while pumping water from the Oasis hand pump earlier this week (I have to give Oasis a negative mark for durability) the pump handle snapped from normal use.

Thankfully the handle from my cast iron pump was a good match and I was able to replace the handle and continue to use the pump without much delay.
Retrofitted pump handle

As a last note for this post, in preparation for the pole beans getting taller, I attached a section of 4x4 fencing panel on the ends of beds 5, 6, and 7 using 2 L-screws on each post pointing in opposite directions to keep the panel in place.  These wood posts are turning out to be quite handy!
Beds with panels added for pole beans

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