Squash Bugs in the Garden

By David Fuller, Colorado Master Gardener, Tri-River Area

Squash bugs (Anasa tristis) are a common pest in gardens that attack various types of cucurbits, including all types of squashes, zucchini, pumpkins, gourds, melons and cucumbers. Squash bugs cause significant damage to plants by sucking the sap from within leading to wilting and death.

Squash bug adult, Whitney Cranshaw,
Colorado State University, Bugwood.org 

The adult squash bugs are a flat, oval shape roughly half an inch long and have a brown or grayish-black appearance. They also have distinctive orange-yellow markings on their legs and antennae. Some also have an inverted V or diamond shape in the middle of their backs with white dots around the perimeter. While mainly seen walking on plants, squash bugs can also fly.

Squash bug nymphs, Gerald Holmes, Strawberry Center,
Cal Poly San Luis Obispo, Bugwood.org 

Adults hibernate under debris in the garden and surrounding areas through the winter. Adults become active and first appear in June when they start feeding on young plants. Once they wake and begin to feed, they then begin to look for mates. An adult female squash bug can lay up to 200 eggs in clusters primarily found on the underside of leaves. Eggs hatch in one to two weeks. After hatching the nymphs have green bodies that change to gray after a few weeks. The nymphs usually feed together in groups on the underside of plants. Nymph to adulthood takes 4 to 6 weeks depending on temperature, relative humidity, and availability of food. Pest populations grow quickly during hot and dry conditions and depending on the location there can be one, two or three generations per season. Adults that develop late in the season do not lay eggs.

Squash bug eggs on the underside of a leaf, 
Whitney Cranshaw, Colorado State
University, Bugwood.org 

Using some of the following methods of control will help reduce the population.

Maintaining healthy plants is the best defense against pest in the garden. Crop rotation, removing plant debris, and covering crops with floating row covers are some effective ways to prevent a buildup of squash bug populations. Good weed control is also crucial to reducing squash bug habitat in the garden.

Another solution is planting nasturtium, natural companion plants that work to repel squash bugs, between plants that are affected by the pests. The parasitic fly Trichopoda pennipes is a predator of squash bugs. The larva will burrow into the body of the host, where it will live for approximately two weeks, at which point it will emerge from the host, killing the squash bug.

Handpicking and destroying squash bugs, as well as their eggs, is an effective way to control them. You can also capture them by using a piece of duct tape. Eggs are usually laid in clusters on the undersides of leaves and are yellow to bronze in color. Once you catch them simply drop them into a bucket of soapy water or step on them.

Neem oil is a natural pesticide that can be used to control squash bugs. It works by interfering with the bug’s feeding and reproductive abilities.

Insecticidal soap is a contact insecticide that works by suffocating the bugs on contact. It is effective against all stages of the bug’s life cycle and is safe for use in gardens. You can also mix your own homemade spray using tsp mild liquid soap to a liter of water (always spot-test sprays before using them on any plant).

Chemical insecticides, such as carbaryl (Seven XLR), permethrin (Permethrin SFR 36.8%) and lambda cyhalothrin (Warrior, Matador) can also be used to control squash bugs. However, it's important to follow the label instructions carefully and to rotate insecticides to prevent the development of resistance.

Squash bug damage, Whitney Cranshaw,
Colorado State University, Bugwood.org 

I have learned that the best time to control squash bugs in the summer heat is after a rain or an irrigation because the bugs will come to the surface, where they can be easier to spray or hand pick. During the summer they will bury down into the soil to get away from the heat, which is why after a rain is the best time to remove the pest.

In conclusion, controlling squash bugs requires a combination of cultural, mechanical, and chemical control methods. Early detection and control are crucial to minimize damage to plants and to prevent the buildup of populations.

Learn more about squash bugs and  from the CSU Extension factsheet: Squash Bug: Management in Home Gardens and find out more about growing squash at this CSU Extension fact sheet Cucumbers, Pumpkins, Squash, and Melons. 

 

Hoppin' to it with grasshopper control

 

Posted by Todd Hagenbuch, Routt County CSU Extension

You’re wondering why an Extension blogger from Routt County, of all places, is submitting a piece on grasshoppers, right? Surely our area, home to amazing snows, Ski Town USA, and pristine, green hay meadows doesn’t worry about hoppers, right? Wrong. Look at this map of the state and you’ll see that our gardeners, ranchers, and wildlife managers all have to deal with the impacts of grasshoppers and the damage they cause more than most of the state.

2021 USDA Colorado Grasshopper Count

You might also be wondering where the data on the map came from. Did you know that the USDA counts grasshoppers on range and cropland to figure out how many there are in areas of the state? In NW Colorado, that job has been done for years by two people who are also Colorado Master Gardeners. As people who understand plants and insects, the two different CMGs who have done this job have been key to the Routt County Extension Office helping local landowners decide if and when they should apply control measures.

Control measures are generally recommended in crops and in range if numbers exceed 15 grasshoppers per square yard. Today my CMG friend and USDA grasshopper counted 43 hopper nymphs per square yard (!) at one site, and another intrepid CMG shared the photo below of hoppers in a dog park in Steamboat Springs. How many nymphs can you count in this area, which is just over a square yard?!?

How many nymphs can you count in this square yard?
Photo Courtesy CMG Donna Segale

As a gardener, you know that just a few hoppers can cause a lot of damage, especially after they’ve molted several times and have become ravenous adults. Large-scale spraying efforts, like I’m recommending for rural landowners and ag producers in Routt County, isn’t as desirable for garden situations, especially if you’re growing veggies. That begs the question: what can I do as a gardener when the swarm is heading my way?

Granular baits laced with insecticides are one way to help control grasshoppers. When the insect eats the bait, they die and become part of the organic matter of your garden. As there is still insecticide involved, however, some folks would like another option. Covering your garden, or at least the rows in it with a lightweight, floating row cover is an excellent measure, making sure hoppers can’t get in but light and air can.

One of the most unusual but coolest control measures I’ve seen involved a two-fence approach, where the garden was located inside a fenced area with another fence located about 15’ outside the inner fence. Each fence was about 6’ tall and not only kept elk and deer out of the garden, but the area between the fences housed about 50 hens who patrolled the area. As hoppers flew in, they were immediately gobbled up by the chickens and rarely got as far as the garden. The ‘chicken moat,’ as the owner called it, was a creative, useful idea that brings me a smile every time I think about it.

If you have grasshoppers, think about creative ways you can limit the damage they do to your yard, garden, or property because they can be a formidable enemy. Also, for more information on grasshopper control, hop on over to CSU Fact Sheets 5.536 and 5.535 to learn more ways to keep this insect at bay.

Mosquitoes and rainstorms and hail, oh, my!

Posted by Carol O'Meara, CSU Extension Boulder County

Just when you thought it was safe to go into the garden, Mother Nature pounds us with severe storms, hail, and tornadoes.  If that weren’t enough, the series of Seattle-like weather has given rise to the scourge of outdoor activity:  mosquitoes.

A gardener’s yard is filled with opportunities for mosquitoes to lay their eggs, since we have pots, buckets, saucers, bird baths, ponds, wheelbarrows, and other accessories stacked around the yard.  If you look at the list many of the health agencies have on common breeding areas, gardeners’ yards appear to be mother ships for these insects.

But there is something you can do to reduce the problem of mosquitoes:  change bird bath water twice per week; dump out water that collects in the dish beneath pots; turn over unused pots, saucers, trays and buckets; and use Bt doughnuts to float in your ponds or water features.  Bt, short for Bacillus thuringiensis, is a natural way to kill off the mosquito larvae in your water.

To protect yourself while working in the garden, cover up or use a mosquito repellent that’s effective against West Nile Virus-carrying mosquitoes. Check with your local health department for suggested repellents. 

Though the gardens love the wet weather, one thing they could do without is the hail that came with it.  If your plants were victims of the savage skies, take heart: it looks bad now but, depending on the plant, its maturity, and time left in the season for recovery, all may not be lost.

Vegetable root crops, such as potatoes or beets, with destroyed leaves could send up new shoots, compromising quality of the crop. In this case the produce may not be worth the growing space.  For leafy vegetables, be patient:  give them at least a week to recuperate after the storm, and if there’s no sign of life, replant.

Flowering annuals stripped of their leaves may not survive, and replanting now will ensure a good display later in summer.  Yes, it’s hard to pull up those babies, so if there are a few bits left on the stem and you’re feeling nurturing, clean them up and a give them a light application of fertilizer.  They might recover.

Severely shredded leaves on smaller perennials should be cut back to the ground, and if the leaves aren’t too damaged, leave them alone.  Bleeding hearts and other perennials with soft stems that look reasonably unharmed should be cut back part way. Generally they'll sprout new leaves along the stem at the junction between the old leaves and the stem.

Work fertilizer in around any damaged perennials that are well established to give them a boost for recovery.  Those with firm stalks should be cut partially back.  If they don't sprout new leaves on existing stems, look for new stems pushing up from their roots.  

Trees and shrubs not pushing new leaves need to be closely monitored; it’s possible they fell victim to the sudden polar plunge we had last November.  Wait until June is almost over before deciding if the plant won’t bounce back from the damage of the freeze.  Examine your woody plants for wounds in the bark or torn limbs; clean up the wound site with a sharp knife and let the plant heal itself. 

Our gardens will recover after this weather, and soon we can relax, enjoying what the dry heat brings:  scorch, blossom drop, and sunburn.

Chickens in the Garden

Micaela Truslove, Broomfield County Extension

My husband and I jumped on the urban poultry bandwagon about two years ago, and we haven’t looked back. Once you get used to the saffron-yellow yolks of homegrown chicken eggs, there’s no going back to the watery, pale yellow grocery store variety. You’ll find no shortage of articles and books touting the benefits of raising your own chickens, and though they do have their challenges, the garden can benefit from a backyard flock.

Compost: Now that it has the nearly undivided attention of our girls, our compost has never looked better. The chickens spend the majority of every day in the compost pile rototilling the contents into wonderful black humus. Hours and hours spent scratching and turning means our compost is done in at least half the time. While they are in the pile scratching around, they are also incorporating their manure. The bedding and manure from the coop also go into the pile each time I clean it out. I try to keep this in the “holding” rather than the actively cooking pile so they don’t have access to it right away. I slowly add the mostly composted material from the bottom of the holding pile into the cooking pile.

Chickens are very curious and get up to all kinds of 

antics. Photo: Micaela Truslove

There are also other chicken byproducts that make it into the pile. Crushed eggshells go out with the kitchen waste and feathers from the bedding and their daily activities are also added. Though eggshells are rich in calcium, studies have shown that they don’t make any significant difference when incorporated roughly crushed. They need to be finely ground, which is more than I’m willing to do. Our soils also tend to be rich in calcium already. If there is a deficiency, as evidenced by symptoms such as blossom end rot in tomatoes, it is usually due to uneven moisture, which inhibits uptake by the plant.

One important note on chicken manure – it should be composted before going into the garden, just like any other manure. This is especially true if the manure is going anywhere near edibles. There are crops that are more risky than others as far as food-borne pathogens are concerned. Those fruits and vegetables that are in direct contact with the soil are more likely to be contaminated than others, and care should be taken to wash produce thoroughly.  This goes for any manure. To avoid possible contamination from harmful bacteria such as E. coli and Salmonella, do not harvest crops for at least 120 days after adding fresh manure.

Weed control: I have to say that this has been a very marginal benefit. One of the things on the top of my “reasons to get chickens” list was that they would help keep the weeds down. It is true that they are voracious omnivores, but they have shown little interest in the most problematic weeds in our back yard. Maybe they’ve decided that there is a steady enough stream of good stuff coming from the house that they needn’t bother with the twisting forest of bindweed that we are plagued with (dang it!).

However, they are fantastic at keeping the lawn nice and short. Grazing is another favorite activity, and they eat grass until they are literally stuffed with it and the blades of tender green shoots protrude from their beaks because their bellies are literally too full to swallow any more. If chickens suffer from a vice, it is most definitely gluttony.

Eating a container of yogurt and fruit that

spent too long in the fridge. With chickens,

nothing goes to waste! Photo: Micaela Truslove

Insect control: We never tire of watching our girls going about their business. They are incredibly curious and a little dippy, which makes for hours of entertainment. One of their favorite pastimes is chasing insects that manage to find their way into the chicken yard . They race around with the unfortunate morsel hanging from their beaks with the rest of the flock in hot pursuit. For some reason they never just gulp it down when they catch it, so there is always a game of keep away before the insect is finally consumed. If I find an army cutworm hiding at the base of a small plant or a grasshopper munching on my lettuce, into the chicken yard it goes and hilarity ensues. They spend a good deal of time after an irrigation tugging on worms in a cartoon-like fashion.

One trend that I recently discovered is the idea of having a “chicken moat” around the perimeter of the garden. The thinking is that the chickens will intercept many of the insects trying to enter, hunting them down like a pack of velociraptors from a movie. They really are quite effective at this, and very quick. It also means that they do not have free access to the garden because they don’t quite understand that it is okay to eat mallow, but I would rather they didn’t decimate the rest of the veggie patch, which they’d do in minutes if allowed. So the pictures you see on Pinterest of perfect raised bed gardens with nasturtiums spilling over the edges and chickens roaming the perfectly manicured pathways politely plucking bugs from the plants while leaving them intact is misleading at best, at least that has been my experience. 

As far as using crushed eggshells as slug control, there are mixed reviews as to their efficacy. Slugs are sensitive to irritants such as diatomaceous earth, which wound their slimy outer coating causing them to desiccate, the evidence is mixed as to whether or not eggshells perform the same function.

Though there are a few challenges to having chickens roaming the garden, we have found that there are great benefits as well, not least of which is the entertainment value. If you are thinking of getting a backyard flock of your own, my advice is to limit their access to desirable plants and instead give them their own space. Allowing them access to the compost pile will do wonders, and will save you a sore back from having to turn the pile regularly. They will keep your insect problems in check and provide plenty of nitrogen-rich manure. One study from the University of Missouri found that one four-pound chicken produces a whopping 28-80 pounds of manure every year! And you certainly can’t beat the fresh eggs.