I lost my planting of spaghetti last year to svb. That is one reason I was so thrilled with the cucurbita moschata varieties that I planted.....I didn't seen a single one of these until almost frost. It was just a happy accident that I planted the these varietes but it will be all that I plant in the future.

For some reason I never have lost cucumbers to them. I do grow them on the fence and dust the bases regularly with insecticide.

Squash Vine Borers are very hard to control and you have to take a multifaceted approach in order to achieve good control. Most people don't give Squash Vine Borers a second thought until they see their plants wilting and dying. To outwit the SVBs, you have to engage in year-round practices that harm them.

With squash vine borers, it is always preferable to be proactive and to do everything in your power to prevent them from getting to your plants. Once they are inside the plant, there is little you can do except slit open the stem and remove them. Some research has indicated that infested plants can have up to 100 SVBs inside them, but I usually only have a couple in any given plant, so slitting the vine open and removing them is pretty easy for a home gardener, but imposssible for someone growing acres of cucurbits.

At the broadest level, you want to use garden system practices to combat SVBs. This can include timing plants very early to try to get a harvest before SVBs arrive and kill the plants, and using succession plantings to give you a harvest after Oklahoma's two separate generations of SVBs are through doing their dirty work.

You also can use cultivar selection. Squash Vine Borers prefer Hubbard Squash above all others. You can use this knowledge to your advantage in a couple of different ways.

1) If you want to raise Hubbard Squash, give it extra attention using Level 2 and 3 practices mentioned below; OR

2) Plant Hubbard Squash outside your regular veggie garden and use it as a trap crop. Hopefully, the SVBs will be drawn to it and you can find them/destroy them on these plants before they move on to the other types of cucurbits in your regular veggie plot. If you are using Hubbard Squash as a trap plot, you shouldn't expect to harvest any Hubbards since they are the 'sacrificial' plants that may give your other plants a better chance of survival.

Another systemic practice that can reduce SVB populations is to manage your garden plot well. This includes prompt removal/destruction of all infested plants, late fall rototilling of soil where cucurbits grew in order to expose overwintering pupae/larvae to predators and weather, and deep incorporation digging or plowing or tilling in spring just before planting. Deep incorporation helps by burying any surviving larvae/pupae very deep in the soil which may prevent them from emerging.

Another systemic practice is to rotate your cucurbit plantings to a new bed or area of the garden each year. This may help some because the newly emerged SVB moths will have to 'travel' to find plants to attack instead of emerging from the soil right there in the squash patch. However, research shows newly emerged SVBs can travel up to 1/2 mile to find squash plants, so rotation may help reduce their numbers or slow them down, but it isn't a 'cure'.

During the SVB season, as soon as you realize a cucurbit plant is dying and cannot be saved, remove it promptly from the garden and destroy it. You can destroy it by burning the plant debris if you are in an area where open burning of brush is not prohibited by burn ban laws or local ordinances, or you can bag up the plant debris and dispose of it with household trash. You also can destroy the SVBs inside the plants by hot composting of the debris.

All of the above systemic practices can help limit the SVB population's ability to survive in your soil and emerge, but those practices won't prevent them. To do that, you need to use another level of good gardening practices: physical and mechanical prevention practices.

At this level, you're trying to keep SVBs that appear in your garden (whether locally hatched or migrating ones) from getting to your plants. For this, you can use any/all of the following:

A barrier product on the ground to keep emerging SVBs from traveling to the plants. You can use newspaper or cardboard on top of the soil surface, or you can use landscape fabric. On top of this type of barrier, place a thick layer of hay or straw mulch or whatever else you have handy. The layer of cardboard/paper/landscape fabric beneath the mulch just makes it harder for the SVBS to emerge easily.

To prevent flying SVBs from landing on your plants and laying eggs, you can use a lightweight (sort of gauzey-looking) floating row cover like Agribon or Reemay but it MUST BE tightly secured to keep the SVBs from getting underneath it. Also, it must be used over beds where cucurbits were not grown during the previous year. Otherwise, you're likely to have SVBs emerge from the soil under the floating row cover. When you use floating row covers, you either have to remove them when it is time for pollination since they will exclude bees and other pollinators, or you'll have to lift the floating row cover and hand-pollinate. If you hand-pollinate, watch very closely for the SVB moths while doing so because they are likely to get on the plants during that few minutes that you are conducting hand-pollination.

One way to protect your cucurbit plants from SVBs is to raise seedlings in containers and transplant the into the ground. At the time you are transplanting, wrap the stems to protect them and be sure your wrapped portion of the stem extends an inch or two underground. Continue wrapping as the plant grows so that you have 6" to 8" of stem above the ground that is protected. You can use aluminum foil to wrap stems if you want, or you can use the legs of panty hose (and they are great because they stretch and expand) or you can use strips of floating row cover. While you want to wrap the entire stem, leave the wrapping loose enough that the stem can grow and expand so it will not become girdled. Stems wrapped in this manner generally exclude small larvae from penetrating and getting into the stem.

Another good practice is to heap dirt over a section of vine every 3 to 4 feet as the vines grow. This will encourage the plants to root into the soil at those spots and that will help the overall plant survive even if you lose a portion of it to SVBs.

Other practices you can employ at this level is the use of moth traps (available at online companies that special in organic gardening solutions), barrier products like Surround (kaolin clay) and the planting of insectary plants to attarct beneficial insects.

Finally, your third level involves the use of certain materials and practicers to directly 'attack' SVBs that are already present in/around your garden.

This includes the use of botanical insecticides like BT 'Kurstaki', spinosad, pyrethrum and DE. However, for the most part, these are only effective if you use them before the larvae penetrate the stems. Once they are inside the stems, you have to slit the stems and remove them and destroy them. Then you bury the slit portion of the stem and water well the next few days so the stem can heal and re-root and hopefully survive.

You can apply beneficial nematodes too. You can mix them with water and apply them to the ground following package directions (they are most effective if applied in early to mid-Spring) and they should attack and kill any pupae/larvae they find in the soil. You also can inject them into infested plant stems. You can inject Bt 'kurstaki' in the same way.

You can spray your plants with Bt 'kurstaki' weekly, and you can spray weekly with insecticidal soap to smother eggs before they hatch. You also can rub a damp cloth up and down the plant stems once or twice a week (I wear disposable latex gloves when doing this) to remove eggs before they can hatch. You can spray the plants weekly with a botanically-derived pesticide like spinosad, pyrethrum or neem but if you use these, be careful with your timing so you don't hurt the bees and other pollinators. You can use rotenone but its use is strongly discouraged because of research that links it to health problems.

You should watch your plants carefully, checking them every couple of days for SVB eggs. Be sure to check the leaf stems because often they are laid there. Remove any destroy/dispose of any eggs your find.

To a certain extent you can control squash vine borers by selecting plants that are less susceptible to them. In order of preference from highest to lowest preference, the SVBs prefer C. maxima, C. pepo, C. moschata and C. agrgyrosperma (formerly known as mixta).

The C. maxima group includes the following kinds of squashes: hubbard, buttercup, Australian blue, turban, banana, zapalito, mammoth (giant) exhibition squashes and a few miscellanous ones that don't fall into any of those groups. Some common maximas include Jarrahdale, Queensland Blue, Triamble, Guatemalan Blue Sibley, Pink Banana and Blue Banana, any variety of Buttercup, Golden Hubbard, Green Hubabard, Red Warty Thing (aka Victor), Dill's Atlantic Giant, Jaune Gros de Paris, Cindarella (aka Rogue Vif d'Etampes) Turk's Turban, Marina di Chioggia, Lumina, Valencia, Fortna White, Georgia Candy Roaster and Galeuse d'Eysines.

C. pepo includes virtually all summer squash (crookneck, straightneck, scallop), acorn squash, Halloween-type pumpkins, nonedible ornamental gourds, zucchini and vegetable marrows like spaghetti squash. The C. pepo group includes Howden, Lady Godiva, Jack-B-Little, Connecticut Field Pumpkin and all other orange pumpkins, Winter Luxury Pie, Table Queen and all similar acorn squash, all Delicata squash, all scalloped/pattypan squash like White Bush Scallop and Benning's Green Tint, Early Prolific Straightneck and all other straightneck and crookneck types, Spaghetti Squash, Golden Zucchini, Costa Romanesco, Cocozelle, etc.

C. moschata includes all the tropical pumpkins, cheese pumpkins, neck pumpkins and japonica pumpkins. Some of the more well-known moschatas are Seminole, Long Island Cheese, Musquee' de Provence, Lunga di Napoli, Golden Cushaw, Japanese Black Futtsu, and Yokohama.

Here in Oklahoma, none of the moschata I've grown have been bothered by SVBs.

C. Argyrosperma (formerly known as C. mixta) includes squashes grown primarly for their seeds and includes most neck pumpkins. These include Green-Striped Cushaw, Jonathan, Japanese Pie Pumpkin (which isn't actually used for pies, by the way), and Tennessee Sweet Potato (which, despite its name is a squash and not a sweet potato).

There is a class of wild squash (C. foetidissima) that SVBs generally ignore.

I've never had SVBs attack my melons or cucumbers although some people say they do. I would assume the same practices used to control them on squashes and pumpkins could be used on other cucurbits.

In my garden, the SVBs always seem to go for the yellow straightneck or crookneck squash and don't bother the zucchini types nearly as much. In the C. pepo group I usually grow Golden Zucchini, Costata Romanesco and Cocozelle and rarely have SVB issues with them.

Dawn

Wow. I think I'm going to have to read that several times to absorb all you said. Thank you Dawn!

So if I mulch really well, I can't do the stem burying- is that correct?

I did the nematodes this spring over the entire bed and I think it helped. I was able to save most of my plants the first time around but I forgot about the second generation and wasn't as vigilant as the summer went on. I lost most of my plants the second go-around.

When I try to cut open the stems and take out the worms I usually end up cutting the whole plant off. I'm not a surgeon! I really like the injectable option in theory but I don't know how effective it is. I guess I can give it a shot (pun not intended) this year and see.

At any rate, I'm going to study your post and figure out which set of options will work best in my garden. Thank you again for sharing all your knowledge with us!

Tigerdawn,

You're welcome.

You can wrap the stems at planting time and then mulch afterwards. Just take a pair of old pantyhose, for example, and cut a part of the leg that is like a tube about 8" long. Pull that tube over the stem of a young seedling that you're about to plant. The hose tube will be loose and bunched up like a cowl neck sweater. Try to bury 1-2" of the hose-covered stem underground and leave the rest above ground. At this point, the above-ground portion is still loosely bunched around the stem where it comes out of the ground. As the plant stem grows taller pull the hose up...just like pulling up knee-high socks. Do this until the hose is 5 or 6" up the stem. You can use mulch, but just keep the much pulled back an inch or so from the stem so you can keep an eye on that stem and watch for the appearance of frass. Normally SVB larvae won't tunnel through that piece of hose. Once the hose is as high up the stem as it can go, use something 'stretchy' to tie it around the stem so it doesn't fall down. You don't want or the larvae to be able to crawl between the top of the piece of hose and the stem. I like to use Wal-Mart sacks cut into strips because they'll stretch out a bit as the plant grows. Or, you can use aluminum foil and it stays in place on its own pretty well.

Mulching is great, except......

If you have squash bugs, it can give them places to hide. So, I'll mulch a squash bed pretty heavily except for the area right up close to the stem. I might have cardboard or newspaper right up against the stem, but not straw or hay or chopped leaves. I keep those materials back an inch or two from the stem so I can see any SVB larvae or squash bugs.

To slit the stem, use something small. I like to use an Exacto knife because it is so small and I can slit the stem without slicing all the way through it. It does take practice and finesse, I'll admit. Sometimes if I think I sliced and cut too much, I'll wrap the "wound"....snugly but not terribly tightly with gauze (or even a band-aid if it is a small wound) and then bury it under the soil. I'll water heavily and usually it will survive.

Many of the techniques used to fight SVBs also help reduce problems with the equally evil squash bugs too. In years when squash bugs are a problem, I lay a board or shingle down under the plant or in a pathway near a squash plant. The bugs congregate under the board to get out of the sun and heat, and then I can lift the bug and either stomp those suckers flat.....or vacuum them up with a portable hand-held vacuum. This works best while they're small, and you have to get them the first time your try because after that they'll run faster and hide when they see you.

Dawn

Thanks for the reminder about the hand-held vacuum. I could have gotten a lot just before frost when they suddenly appeared on some bad LI squashes I had left in the row.

I turned the chickens loose in the garden about a month ago and they are wreaking havoc with the mulch. I am hoping they are finding bugs and eggs and eating the heck out of them.

I believe I've seen that wild squash (C. foetidissima) in Mexico. Once, I cut one open and touched the insides with my tongue. Whoooeee! My mouth was puckered for hours! No wonder SVBs don't bother that one!

I've laid down aluminum foil around the base of non vining squash plants. It hasn't been a scientific experiment, but, in three or four tries, I've never lost one of those plants to SVB.

For acorn squash I've found Scarchuk's Supreme to be resistant to SVB. They attack it. But it usually survives & produces. Dolma Kabak, is a vining summer squash (c. pepo) which does the same. Years ago I grew Erkin, which is a Turkish summer squash (c. pepo & non vining) which also tended to resist them.

But for me, the best strategy is to focus on c. moschatas. They often make it through the season with no damage, or very little.

George
Tahlequah, OK

Glenda,

I bet those chickens are having a good time and eating lots of insects eggs and insects.

When we rototill beds in the garden, the chickens like to follow along behind us and dig and scratch through the newly fluffed up soil looking for yummy goodies.

George,

We have the wild buffalo gourds here in southern OK and I used to see them in pastures occasionally in Texas when I was a kid. I was never brave enough to try one of the gourds.

I see them here in Love County when we are out at wild fires in remote places, and especially in wildlife management areas along the Red River.

As far as I know there aren't any growing here in our neighborhood because most of the ranchers use broadleaf weedkillers to get rid of stuff like them, and I guess that is a good thing. The C. foetidissima flower pollen can be carried from those plants to cultivated cucurbits, so that could be a problem for anyone trying to save seed.

I've linked an article with some photos of them. I've only seen them in the green stage. Guess I've never been around them when they have matured to the yellow color. Just look at the size of the root in the link! I guess that explains why often you'll see green buffalo gourd plants in pastures where everything else is brown and looks dead because of drought. The year I first saw them while out at wildfires along the river was in July 2006 and everything else was brown because of 2 years of drought. The buffalo gourds, though, were just as green as they could be, although their green is a dusty-looking grayish-green.

Dawn

Here is a link that might be useful: Buffalo gourd