Squash

[Bill Norton]

Help,

I planted a bunch of squash in a raised bed (which great soil and eco friendly feed) and we've seen them go from weak and yellow, to beautiful and green - but last week they turned again, several have died and not I'm seeing the base of the plant looks like it's either rotten or dying - I don't know if this is a fungus (none of the other plants have it ) or whether it's being eaten, or too much water....does anyone have any experience with this issue? A picture is attached of the base of the plant - the torn up area is killing the plant..

Thanks
Bill

[Rachel Butler]

Hi Bill - I did a little research and it sounds like you have a pest - the Squash Vine Borer. I have compiled some of this information from the Austin Permaculture Group. (thanks amigos)

From the conversations I have been in, there is not a whole lot one can do about it. Vine squashes such as butternut and tatuma are less susceptible because they tend to root every place they touch the ground, which means the SVB does less damage. They tend to appear mid-May through June, and again in August. So, plant really early, harvest like crazy and expect to lose the plants.

Below are some excerpts from Dr. Bob Randall's (former director of Urban Harvest in Houston) book of Year Round Vegetables, Fruits and Flowers for Metro Houston ref the dreaded squash borer:

Squash vine borers are grub larvae that eat out the inside of squash and pumpkin vines and kill them long before they have produced their last fruit. They come from eggs laid by a red orange backed fly-like moth about a finger joint in length. The squash vine borer destroys squashes between late May and mid September every year, but there are no simple, cheap, effective poisons other than the synthetic products like Sevin. ... Poisons are another approach that is time consuming. Sabadilla or pyrethrum put on the stem every week will usually work. A dangerous chemical poison like Sevin stops them so well that it is the usual approach among chemical gardeners. I consider Sevin too dangerous to use....

...Tatume squash and all tropical squashes are totally immune to the borer, and tropical pumpkin/calabasa often outgrow it.

... there are other ways to defeat borers. Planting keeper (winter) squash in mid July and summer types in mid-August to mid-September eludes borers after late August. You can protect the vine for a month with row cover but this probably isn't necessary. You can also stop borers very effectively, but expensively, by injecting beneficial nematodes into the stem of the squash. From mid-April to mid-September, inject the plants with an agricultural syringe or a furniture glue injector. Do this just before the flowers first open, then twice a week thereafter. Inject about 2.5" from the root before there is 'sawdust' indicating there is damage.

... you can also stop borers with mass plantings. Borers do not bother very large plantings of squash. If you plant 400 or so plants, you won't have borers (No Joke).

...You can also help reduce the problem next year. Don't plant where the vines were last year and destroy cocoons when you find them in the winter soil. Bury or compost old vines to destroy borers. Try not to plant squashes where there were some in the last 3 years.

Another suggestion, rather that nematodes inject Bacillus thuringiensis (Bt) - The biological pesticide Bacillus thuringiensis is a beneficial bacteria applied as a spray to kill caterpillars. Sold under a variety of names such as Thuricide, Dipel, Bio-Worm, and others. Use Bacillus thuringiensis 'Israelensis' (Bti) in water for the control of mosquito larvae.

Thanks - Rache!

[Bill Norton]

Damn Squash Vine Borer -I knew this was serious. I've seen the red orange backed fly-like moth and we back up to a green space - not getting away from the bugs. Thanks for all the helpful information!!
Bill