Aphid Advisory

Several years ago I signed up to receive advisories put out by the Utah State University. These advisories are centered around the principle of Integrated Pest Management.

Today, I received this advisory on aphids which at first seemed very odd for this time of year, until I read it. Very interesting. It seems that this past years’ weather patterns (cool, wet spring that is now being followed by a dry, warm fall) has resulted in all kinds of “unusual” insect activity in northern Utah for 2010.

From the advisory:
“It is normal for aphids to take flight in late summer and early fall for egg-laying, but the numbers that are occurring now are far beyond “normal” populations. Starting about a month ago, they started swarming, from the mid-section of Utah to Brigham City and parts north. Winged aphids are covering people’s clothes, cars, and falling like rain. Wingless aphids are feeding on tomatoes, peppers, fruit trees, and ornamentals. A variety of species have been identified, including witch-hazel gall aphid, bird cherry-oat aphid and related species, leafcurl plum aphid, mealy plum aphid, and green peach aphid, all of which are migratory, multi-host insects with an intersecting life cycle.”

I had no idea, first off, that there were this many varieties of aphids and secondly that they could travel as far and wide as they do. Winged aphids can travel hundreds of miles with assistance from low level jet winds.

Some more interesting facts:
• Eggs that hatch in spring on the primary host (usually a woody plant) are all females.
• Once fully grown, those female adults give birth to live female nymphs that are genetically identical to themselves.
• This process continues for several generations on the primary host until overcrowding, causing adult females to give birth to female offspring that form wings.
• These winged females leave the primary host for herbaceous plants for the summer, such as weeds, a field crop, perennials, or vegetables. There, they spend the summer, continually expanding their population through live birth to wingless females.
• As the day length shortens in the fall, adult females are once again triggered to produce large numbers of winged offspring, which this time, are both male and female.
• These winged aphids then migrate back to their preferred primary host for feeding and egg-laying. The winged females give birth to sexual females nymphs, that, when mature, are able to mate with the winged males that migrated from the herbaceous hosts. These females then lay eggs for overwintering.

Their ability to survive is nothing short of amazing. But then, I am constantly in awe of how nature can devise creative methods of adaptation to ensure its survival.

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Attracting and keeping beneficial insects

Quick, what do you do when you see insects in the garden? Do you cover everything with netting hoping to keep them all out? Do you reach for the pesticide hoping to rid them all with extreme prejudice? Hopefully, you don’t do either of these things until you know if they are beneficial or harmful. As a gardener, it would be to your benefit to know the difference.



Beneficial insects are on your side when it comes to controlling those harmful nasties that we all love to hate. But they wont stick around in your garden unless they have a welcome environment in which to live, especially when the harmful insects are not there.

Some beneficials have voracious appetites when feeding on other insects, some parasitize them by laying eggs in the host body giving their young a food source. Isn’t nature just delightful?

Beneficial insects may consume large numbers of pest insects, but their diets are not limited to other insects. Keeping them around when there are no insects to prey on is a matter of providing the right shelter and the food they need. A term I recently learned that describes such a haven is: insectary. A small garden plot of flowering plants designed to attract and harbor beneficial insects. Think of it as a garden within a garden. Often set off to one side in an out-of-the-way area that doesn’t get disturbed by regular cultivating and weeding. A wild place that these friends of ours can call their own.

Many beneficial species have periods in their life cycles when they survive only on nectar and pollen. Therefore, planting a variety of insectary plants with different bloom times and different bloom sizes will ensure an adequate supply of nutrients to keep the beneficial insect population going strong.
The tiny flowers of fennel (left), angelica, yarrow (right), coriander, rue, dill, and carrot are suitable for parasitoid wasps. Insectary plants also include those plants that provide another critical need, shelter. Providing plants tall plants will help protect flying insects while low-growing plants, such as thyme, rosemary, or mint, provide shelter for ground beetles and other beneficial insects.

The plot does not have to be large, just big enough to hold 6-7 varieties of plants which attract insects. Once the garden has matured you can watch your personal insect security force do the work for you.

Creating your habitat can add color, texture and height to your garden. Start luring beneficials early in the season with annuals like alyssum, cosmos, zinnias, sunflowers, and marigolds. At the same time, set out perennial flowers and herbs, including golden marguerite (Anthemis tinctoria), yarrow, lavender, mint, fennel, angelica, dill, parsley, and tansy. When you've finished harvesting allow cilantro, cabbage, brussel sprouts and carrots to flower providing nectar to act as a treat for a job well done.

Some gardeners refer to the insectary as a form of ‘companion planting’, based on the ability of a plant to draw a beneficial insect toward another plant that is susceptible to pest damage. The plants can be inter-planted among your regular plants and serve the same purpose. They may plant alternating rows of insectary annuals with rows of vegetable plants. I have seen an ‘island’ of insectary plants with vegetables planted around them in a circle and vice versa.

Insectary Plants
- - Beneficial Predators Attracted

Achillea filipendulina
- - Lacewings, Aphidius, Ladybugs
Alyssum
- - Hoverflies, Lacewings, Tachnid flies
Amaranthus
- - Ground beetles
Anethum graveolens (Dill)
- - Ichneumon wasp, Ladybugs, Lacewings
Angelica gigas
- - Lacewings
Chamomile
- - Parasitic wasps, Hover flies, Robber flies
Convolvulus minor
- - Ladybugs, Hoverflies
Coreopsis
- - Hoverflies, Lacewings, Parasitic wasps
Cosmos bipinnatus
- - Hoverflies, Parasitic wasps, Lacewings
Daisy
- - Parasitic wasps, Hover flies, Robber flies
Digitalis
- - Dicyphus
Daucus Carota (Queen Anne's lace)
- - Lacewings, Ladybugs, Hoverflies
Foeniculum vulgare (Fennel)
- - Damsel bugs, Ladybugs, Lacewings
Helianthus annulus
- - Pirate bugs, Beneficial mites
Iberis umbellate
- - Hoverflies
Limonium latifolium (Statice)
- - Hoverflies, Parasitic wasps
Lupin
- - Aphidius, Aphidoletes, Hoverflies
Melissa officinalis (Lemon balm)
- - Parasitic wasps, Tachinid flies
Mints
- - Parasitic wasps, Hover flies, Robber flies
Petroselinum crispum (Parsley)
- - Parasitic wasps, Hover flies, Tachinid flies
Scabiosa (Pincushion flower)
- - Hoverflies, Parasitic wasps
Shasta Daisy
- - Pirate bugs, Beneficial mites
Sunflowers
- - Pirate bugs, Aphidius, Parasitic wasps
Tanacetum vulgare (Tansy)
- - Ladybugs, Lacewings
Verbascum thaspus
- - Dicyphus
Yarrow
- - Hoverflies, Parasitic wasps, Ladybugs

If you have used selective pesticides in the past, you may have chased away beneficial insects as well and so you will have to wait at least a couple of years before a natural balance between beneficial and pest insect population is achieved. In the meantime the pest population may grow to a scary size and seemingly out of control but soon predators will come in and begin feasting. While you are waiting, you can use Bt, Neem or insecticidal soap to help manage them. Just keep in mind that this balance between beneficial and pest insects existed for millennia before we came along and it will return if we provide enough variety.

Your success will probably vary from year to year as the climate and vegetation change and new pests arrive. You should expect the development of a habitat where pests and beneficials exist in a rough balance to be an effort of several years rather than a season or two. Despite the presence of so many beneficials, you will still need to hand-pick squash bugs or rub scale from the branches of the fruit trees.

While your insectary matures, you can:
* Provide water areas with shallow dishes or pebble areas. The larger good guys, toads, will appreciate these areas too.
* Include some permanent hardscapes such as stone paths and decorative rock.


Common beneficial insects.
First, learn how to recognize common beneficial and pest insects.

Lady bugs, or lady beetles, prey on aphids and other soft-bodied insects. These must be their favorite meal because ladybugs can consume up to 50 aphids per day.
The larvae will each eat close to 400 aphids before entering its pupal stage. There are many species of lady beetle that attack many different prey. The adults are independent, flighty creatures and may not all stay in your yard, but if they eat aphids in the neighbors yards then at least that’s a few less aphids for you to worry about.

Ground beetles (carabus nemoralis)-don't fly much, preferring to run away when disturbed. You probably won't see them unless you uncover their hiding places, usually old piles of weeds. They're relatively large (about 3/4 inch), and dark, with long, jointed legs. They're nocturnal hunters, rooting among leaf litter for insect eggs and larvae.

Soldier beetle (rhagonycha fulva)-show up for the late spring aphid feast.










Rove beetles (tachyporus)-feed on mites and snails and inhabit piles of decaying organic matter. They are similar to thrips, but without the ‘pincers’ on the back.



Lacewings-Watching these graceful, almost butterfly-like adults searching for pollen or nectar, it is difficult to imagine it in its fiercely predacious larval stage, during which it devours aphids, caterpillars, mealybugs, leafhoppers, insect eggs, and whiteflies. It even eats other lacewings.

Up close, the lacewing larva looks like a tiny (1/2 inch) alligator. If you keep a supply of flowering plants, adult lacewings may take up residence. If you decide to introduce beneficial to your garden, lacewings are the most effective predators you can buy.

Hover flies-With their striped abdomens, hover flies look like small bees, but they move through the air more like flies, zipping from plant to plant, hovering briefly before landing. Some people call these sweat bees since the flies enjoy a little tasty drink of sweat periodically. The hover, or syrphid, fly is one of many predatory flies and one of the most conspicuous beneficial in our garden. They can be found just about anytime and anywhere in the garden. They visit a variety of flowers in search of pollen and nectar, and they lay their eggs near aphids or other soft-bodied insects. The eggs hatch into ravenous larvae that eat up to 60 aphids, thrips and small caterpillars per day. The adult hover flies do not eat other insects, but feed on nectar and pollen.

Praying mantis-undoubtedly the most well known garden dweller, this insect is a master of the hunt and at camouflage. Larger species have been known to prey on small lizards, frogs, birds, snakes, and even rodents. Back in my home state of Indiana, we used to find these growing 5-6 inches long.





Parasitic wasps-These very helpful creatures, ranging in size from small to minuscule, will defend your garden against caterpillars like corn earworm, tomato fruitworm, cabbageworm, and tent caterpillars. The smallest and perhaps most popular parasitic wasp is the trichogramma, a dust-size creature that lays up to 300 eggs in moth or butterfly eggs. You can buy them through the mail if you're expecting an infestation of caterpillars. They don't live very long so timing their release to coincide with the presence of pest eggs is pretty important.

Spiders. All spiders feed on insects and are very important in preventing pest outbreaks. The spiders normally found in gardens do not move indoors, nor are they poisonous. Permanent perennial plantings and straw mulches will provide shelter and dramatically increase spider populations in vegetable gardens.

Tachinid Flies. Although they look similar to house flies, tachinid flies are very important enemies of cutworms, armyworms, tent caterpillars, cabbage loopers, gypsy moths, sawflies, Japanese beetles, squash bugs, and sowbugs. Grow pollen and nectar plants to attract them.

Predator insect populations will vary in size according to the amount of available food much the same way pest populations arrive when their favorite treats are available.


Beneficials by mail
Many beneficial insects are available by mail. You might find it useful to release a few to get a jump start on pests while your habitat is developing.

Perhaps the most effective and economical are lacewings, available as eggs, larvae, and adults. A thousand lacewing eggs, enough for 2500 square feet, will cost about $5 plus shipping. A thousand larvae cost about twice that.

Lady beetles are widely available in garden centers or by mail. Five hundred will cost you about $7.50. Remember to have some aphids and pollen around before you release them, and don't be surprised if many fly away.

Trichogramma wasps are available in the form of parasitized eggs glued to a card. In the event of a caterpillar invasion, you hang the card in the garden, the wasps emerge, and you're on your way to victory. It's important to consider, however, that trichogramma will attack butterfly larvae, too. Timing and accurate pest identification are very important. A card with 100,000 eggs costs about $15.

Minute pirate bugs and big-eyed bugs are available, but very expensive.

Keep in mind that if you don’t have a food source for these insects they are not going to stick around. They just might find your neighbors yard more to their liking.

Once you have put your faith in beneficial insects, the next time you see a cloud of whiteflies around your cabbage or a crawling mass of aphids on your roses you can rest easy knowing that hover flies and lady bugs will soon move in to feed and deposit their eggs on the leaves. New hover flies will emerge in a few days and begin looking for pollen and nectar. A large Asian lady beetle is grazing through the crowd. I guess I can relax. It looks like the insects have this outbreak under control.

In summary, beneficial insects provide an undeniable service by 1) protecting our valuable and desirable crops from pests, 2) eliminates our need to introduce chemicals into our environment, and 3) gets us to expand our garden variety by adding plants that we probably would not have considered adding. All for free. Quite a magnificent plus if you ask me.


Further reading:
The Bugman on Bugs This sequel to the authors’ Ask the Bugman (2002) contains more valuable information on how to identify assorted insects and arthropods and the best ways to keep them out of your house, all presented with the wry humor that fans of Fagerlund’s nationally distributed newspaper column have come to treasure.

Great Garden Companions: A Companion Planting System For A Beautiful, Chemical-Free Vegetable Garden
Let master gardener Sally Jean Cunningham show you how to keep pests and diseases at bay with her unique companion-gardening system. By planting special combinations of vegetables, flowers, and herbs, you can minimize pest and disease problems and create a high-yielding, beautiful garden!


Other helpful resources
Biological Control: A Guide to Natural Enemies in North America

Biological Control Systems

The Beneficial Insect Company

Companion Planting

Garden Toad’s Companion Plant Guide

Insect Identification
Dave’s Garden

What’s That Bug

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Pruned roses

Gave the roses their annual Spring pruning. I always look forward to this part of Rose maintenance with trepidation. First of all, I know that it is necessary for their health but I am still such a rookie that it just seems I am killing them when I trim them back as harsh as what is recommended. Secondly, I have seen what incorrect pruning can do to rose bushes and it isn't pretty!

In speaking with the neighbors I learned that the bushes had not been pruned for the last several years before we moved in, (the family was going through their own personal turmoil which I won't get into here) just suffice it to say the roses took a back seat for a couple of years.

Having pruned them now for a couple of years and seeing that they are still growing I guess I’m doing okay by them. It’s difficult to follow a book for instruction because I don’t have the perfectly shaped rose bushes to start with. I just cut off all of the winter damage and don’t worry too much about creating show quality shrubs.

When we moved into this house in the Summer of 2004 there were four Roses, I don't know for certain what kind, my guess is they are floribundas, but shrubs anyway, not climbers, with lots of small, deep red flowers. They looked really sad. Anyone could see that something had to be done to save them. They are planted in full sun (which is good), too close to the house (which is bad due to lack of air circulation), without any mulch (which is bad due to loss of water in Summer months), in hard clay (which is amazing they have survived!)

The flower color is beautiful, (this hto was taken last year). Aphids had misshapen the flowers petals, there were spots on the leaves, which I have learned is black-spot and some grayish powder which I learned is powdery mildew. All of these three problems have detracted greatly from the overall beauty of the bushes. So, not only was I faced with learning how to start dead heading them properly, I was now faced with having to learn how to stop these three very common maladies of Roses. The internet is a wonderful tool for these two purposes as well the public library.

That first summer my wife and I decided that two of the four bushes were just too far damaged to save and we were afraid that in keeping them we would be jeopardizing the healthiness of the other two. They were all planted within a 100 sq ft plot. We pulled those two out and began to nurse the other two back to health. I knew my first course of action was to get some mulch on the ground to help keep the roots cool. After dumping some small bark mulch and spreading it to about three inches deep (being careful to keep it away from the main stems) I began reading up on the control of aphids. That part was pretty easy, just spray the bushes with a hard stream of water but I read that insecticidal soap works well and thought that they might need this because they have had such a big head start in building up their colonies.

Next, I began reading up on pruning and controlling diseases of roses. The first thing I was surprised to learn was that the way you dead head determines how a rose bush blossoms. I thought this was predetermined by the type of rose you have. I don't know about most people but I really don't have a huge preference towards fewer, large flowers or more, smaller flowers and since these had not been dead headed by the previous owner these bushes produced a lot of smaller flowers. Plus, since they had not been well-cared for, I was also surprised that they had so many flowers!

Two years ago, Spring 2005, was the first time I had the opportunity to put what I had been reading on pruning to the test and I must confess I was afraid to cut them back as hard as they really needed. We began using Safer Soap whenever we saw aphids, we were careful to water them only in the morning, dead head them as soon as the flowers were fading and added as much compost as we could to help break up the clay.

We were confident enough that we were doing everything right that we bought two more floribunda roses to replace the two that we threw away. We went with Jackson and Perkins 'Tuscan Sun' and 'Honey Perfume'.

Tuscan Sun


Honey Perfume


In the Spring of 2006, we pruned the two older roses a lot harder than we did in Spring 2005 and I was astonished at how quickly they grew back and at how much fuller they looked. Within one month, there are a lot of leaves and new branches.

The two new roses were not to be pruned the first year so we just let them go. The aphids don't even get a chance to get fat any more because we spray those bad characters off as soon as we see them. We stopped using the insecticidal soap, we just spray the bushes with a hard stream of water and use Bayer Advanced 2-in-1 Rose and Flower Care Granules.

I learned that feeding them well and at the correct time works wonders in controlling black-spot I also add Epsom Salt to get the leaves shiny. We spray the plants regularly with a milk-based spray to control the powdery mildew. And, I'm sure that the regular application of clay busting compost has had a lot to do with their overall health. After all of this routine care we were rewarded with flowers even more beautiful than we had imagined.

But something was wrong with the 'Honey Perfume'. It was planted the same day as the 'Tuscan Sun' but on the South side of the shed in the back yard instead of the South side of the house in the front yard. To me, the sitings were identical so there must have been something else going on. It bloomed nicely, at first, but towards the end of the summer the blooms were not looking as good as they should have. I can't figure out what it is but I decided to move it to the South side of the house with the other three roses before it just dies off. Hopefully I am doing the right thing because leaving it there is definitely not the right thing. So, I have to wait and see and keep my fingers crossed. It looks really quite sad. There are three gray sticks reaching up to about one foot tall and there are holes in the center of each stem. I learned that Rose Cane Borers could have created the holes. I put Elmer's Glue over the holes hoping this is the right thing to do. I don't know if they over-wintered there (maybe putting the glue on will suffocate them) or if they ate all of the life out of the plant and moved on already. But one important thing I have learned about nature is to never give up! I have seen plants come back from sticks before and I'm not as ready to give up on these sticks as I was three years ago with two of the original roses at this house.

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