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Q. My peach trees struggled this year. The fruit set was very sparse, and the fruit that did make was inedible due to disease and bug holes. Can you provide some tips to hopefully prevent a repeat of last year?Photo credit – Chris Becker, Alabama Extension
A. I am so glad that you asked this question now. For some folks, their peach trees are the last thing on their minds in fall and winter. However, there are some steps that you can take now to help alleviate a lot of problems when spring does roll around. Also, now is a great time to develop an annual maintenance plan to make sure that each season is a “fruitful” one.
Right now, you should be thinking about steps to controlling insects and disease. If any fruit fell to ground this year, pick it up and dispose of it. Diseases can over-winter on fallen fruits. Fungal diseases are prevalent in our climate so it’s difficult, even with cleanliness, to grow peaches in Alabama without a spray program. More backyard fruit trees die from pests that could have been prevented with dormant sprays than from any other cause. In mid to late winter, you should make your first “dormant oil” application, making sure that the air temperature is above freezing. Three weeks later, you should make a repeat dormant oil application. As winter moves into spring, peach trees should be sprayed with a fungicide (like copper or chlorothalonil), just prior to flowering. This step should be repeated every 2 weeks until harvest. Additionally, an insecticide should be applied in 2-week intervals AFTER the blooms fall from the trees. This prevents peach curculio, fruit moth, and others. These applications should occur until harvest, as well. Timing of the insecticide application is crucial so that beneficial pollinators are protected.
Another important step in proper peach maintenance is correct pruning. Peaches should be trained to the open-center system. A properly pruned peach tree will have an upside-down umbrella shape. Remove any diseased or broken branches as well as all vigorous shoots growing upward or crossing over the middle of the canopy of the tree. Now, you know how to prune, but what about timing? Peach trees should always be pruned in mid- to late February, after the threat of freezing weather has passed. This process should take place just before trees leaf out. Pruning too early in the season encourages bacterial canker and could lead to tree death.
Adequate fertilization is essential to peach tree success. In early March, you should apply a cup of 10-10-10 (or similar analysis) fertilizer per year of tree age. Do not exceed a maximum of 10 cups for mature trees. In August, after all fruit is harvested, apply a cup of calcium nitrate per year of tree age, not exceeding 4 cups for mature trees.
One other tip is directly related to fruit size. The greater the number of peaches on the tree, the smaller those peaches will be. To prevent limb breakage and ensure fruit quality, you should thin peaches about four weeks after full bloom, or just after the natural “May” fruit drop. Hand-thin peaches, leaving about 6” between the remaining fruit on the tree.
I hope these tips are helpful. Yes, I know that it might be a little early to talk about peaches, but developing a maintenance plan now is essential to ensuring a bountiful harvest later. Happy gardening!
Written by Bethany A. O’Rear of the Alabama Cooperative Extension System (ACES).
"The History of Corn" probably sounds like a topic too esoteric to be anything but a good sleep aid. The history of corn is in fact an interesting and inspiring one. Corn as we know it today is not a product of the natural world, but rather the culmination of thousands of years of human ingenuity and applied horticultural knowledge. Generation upon generation of selective breeding has produced one of the most important food crops on Earth, with more corn produced worldwide every year than any other cereal product and corn being the number one agricultural product produced in the United States. This global super crop can trace its humble begginings back to central Mexico, where it originated from a diminutive grass called teosinte. [photo credit: John Doebley, https://teosinte.wisc.edu/images.html]
At first glance, teosinte appears about as different from modern corn as a wolf from a pomeranian. The most obvious difference is its branched growth, with each branch ending in a single female flower which produces a kernal. These may eventually develop into small ears, formed of a single stack of unfused kernals. Also unlike the ears of modern corn, those of teosinte are not husked and only about one inch in length. Before cultivation, these plants would typically produce just one "ear" at a time. It was around 10,000 years ago that early farmers began to notice that some plants produced more kernals than others, or that some kernals were tastier than others, and so they began to save and replant only the seeds of those plants with these decidedly superior fruiting habits. This selecting process continued over thousands of years, eventually resulting in plants which could produce multiple ears at a time, each several inches long and containing numerous large, fused kernals. These plants are what we know today as corn, or maize. Teosinte still exists in its native range to this day, but it is endangered and the number of individual plants is dwindling.
From Mexico, corn spread northward to what is presently the Southwestern United States, and southward to what is presently Peru. In North America, selective breeding (via cross-pollination) continued for many more generations to produce corn plants suitable for colder climates. These plants were bred to produce ears within a much shorter growing season. Eventually, by crossing and selecting plants that produced ears earlier in their growth, Native Americans developed corn plants which matured within three months after planting. By the time Europeans first made the voyage to North America and encountered its native residents, corn was already a major part of the native diet. You probably know the fabled story of the first Thanksgiving, but did you know corn was likely served as a porridge sweetened with molasses?
From the New World, corn was one of numerous crops traded between Native Americans and European settlers starting with Christopher Columbus. Today, corn is grown around the world and exists in a number of forms such as the sweet corn grown for human consumption, field corn grown for animal feed, and colorful flint corn (also known as Indian corn or ornamental corn), of which popcorn is a variant. Corn, so important to the diets of the Native Americans who first cultivated and developed it, is now ubiquitous to many cultures.
Aside from its food value, 40% of the corn produced in the United States is used to make corn ethanol. It is mainly used as an additive in gasoline, and some vehicles are capable of running on 100% ethanol. Corn is also used to make numerous industrial products including pharmaceuticals, fabrics, makeup, explosives, paper goods and paints.
The history of corn continues with genetically modified varieties which accounts for 85% of all corn planted in the United States as of 2009. These varieties are engineered to tolerate damage from herbicides, insect pests, diseases, and drought.
The story of corn is a significant piece in the story of humanity. When our ancestors were hunting and foraging in the harsh wilderness of several continents, corn's own ancestor was growing wild and free. Then came our shared journey into the world of agriculture leading to the rise of modern civilizations. Now, man and corn walk leaf-in-hand into the world of tomorrow. This holiday season, remember all that we and corn have been through together, all that corn has given us, and offer corn the respect it is due.
How much water do you use a day? Would you believe 60-80 gallons is an average amount of water used per person per day?
There are simple habits we can adopt to conserve our water use at all times, but especially in times of drought. Watching water use in our homes makes a difference in making a limited resource go further.
Inside the home water savings:
1. Take short showers instead of baths or only fill tub ½ full.
2. Install water saving toilets and showerheads.
3. Turn the water off when brushing teeth, shaving, washing dishes, and more.
4. Wash clothes and dishes only when you have a full load.
5. Waiting for the water to get warm? Catch that cool water for plant watering.
6. Check for leaky toilets and faucets that waste water.
Outdoor water savings:
1. Limit outdoor watering to the coolest part of the day. Consider using soaker hoses or trickle irrigation for trees and shrubs. Grass can go dormant in dry times and recover when normal rainfall patterns return.
2. Check irrigation systems for correct adjustment and leaks.
3. Group plants with similar water needs in the landscape and consider drought tolerant plants.
4. Mulch around shrubs and in flower beds to retain soil moisture.
Learn more ways to reduce your water usage here. You can also keep up with all the latest drrought information for both consumers and farmers at www.AlabamaDrought.com.
Timely Information pub:
2016 Water Conservation timely info.pdf
By Bethany A. O’Rear
Q. Autumn is my favorite time of year. The air is getting cooler, the holidays are just around the corner, and the leaves, even though this year’s drought has subdued the brilliant hues that we know and love, still put on a colorful show. However, all too soon, they flutter to the ground, bringing with them the annual question, “What can I do with all of these leaves?” Other than taking on the monumental task of raking and bagging, do you have any suggestions?
A. I love this time of year as well. I always look forward to fall’s brilliant display of color, but, as you mentioned, the drought has taken a toll on how vivid our fall appears this year. Additionally, it has also caused leaves to drop earlier and in greater numbers. Instead of sporadically falling over several weeks, many landscapes have seen a deluge of leaves hitting the ground all at one time.
Who among us didn’t grow up with the yearly task of raking and bagging leaves for disposal in the landfill? While it was hard work, the occasional dive into the leaf pile made it almost worth it, but, this method is not a good use of our natural resources. Other folks still rake and burn their leaves, which is not only a waste of valuable organic matter, but can also become a fire hazard, depending on the amount of rain that has fallen. This is especially true this year, due to the fact that 46 of our 67 counties are under a burn ban.
There are several other options for leaf disposal. A great way to make use of all of those leaves is to turn them into mulch, and the best method for accomplishing this is by using the lawn mower bagging attachment. The mower helps to shred the leaves, making them less bulky, and more easily handled. After shredding, you can spread leaves around the bases of trees and shrubs, or in your annual and perennial beds to cover any bare soil areas. The gradual decomposition of this leaf layer will result in the addition of valuable organic matter to your soil, as well as moisture conservation and reduced weed growth. One point to consider – leaves break down fairly quickly as a mulch layer. Consequently, you will need to add material a little more often than you would if using bark mulch. If you are like most of us, you have a bountiful supply, so that should be no problem!
Composting is another option for the disposal of all of those leaves. If you have a compost bin, fill it in the fall and keep any remaining leaves in a holding bin or in plastic bags stored nearby. As leaves settle in the bin, continue to add the remaining leaves. Leaves, in their natural form, are somewhat difficult to decompose. Shredding the leaves will be a tremendous help to the decomposition process. You can also speed up the process with the addition of microorganisms. By incorporating a few grass clippings, composted manure, or fertilizer into the compost bin, the leaves can be reduced to a rich organic amendment for your future gardening needs.
If you don’t have a compost bin, you can create a compost heap, which is simply a free-standing pile of leaves. A good, workable size for a compost heap is about 3 feet wide and 3 feet high. The length can vary according to the amount of leaves used. Once again, the rate of decomposition depends greatly on the size of the material to be composted. Shredding leaves will significantly help to speed the process.
A third option is to incorporate leaves into the garden this fall. After spreading a leaf layer (about 2” thick) over the garden, work the layer into the soil. Then, let nature takes its course. The leaves will decompose over the winter, resulting in rich, dark garden soil by next spring.
So, there are several answers to your all too familiar question. Choose the one that works best for you. Just make sure to enjoy autumn’s last burst of color before it fades away.
written by Bethany A. O’Rear of the Alabama Cooperative Extension System (ACES). She is housed at the C. Beaty Hanna Horticultural and Environmental Center, which is based at the Birmingham Botanical Gardens. Other Garden questions? Call the Master Gardener Helpline, 877-252-4769.
By Andrew J. BarilIt began a week or so ago. In the middle of the night, before the rays of sunlight early Friday morning, I heard a plunk on our roof. This is a sound I know well. My wife and I have been living in our little mountain cabin for almost ten years now. I’ve heard this sound before. For the months of October and November, I will be hearing the plinking of oak acorns and hickory nuts on our metal roof.
Here at our Talladega cabin we have a host of oak trees. We have black, blackjack, cherrybark, chestnut (mountain), northern red, post, southern red, water, white, and willow oaks. We also have mockernut, pignut, and shagbark hickories along with a whole host of additional hardwoods. According to one of Extension’s publications; “Management of Hardwood Forests for Timber in Alabama”, we have around 200 different hardwood species in Alabama, including 28 oaks and 8 hickories. Because Southern Pines so dominate our timber industries, many people tend to overlook hardwoods. However, based on US Forest Service inventory research, hardwoods comprise the majority of Alabama’s standing timber volume.
Most of our forest wildlife friends value these hardwoods for food and shelter. Most of the food value is found in the leaves and seeds. Leaves are eaten mainly by insects that in turn are eaten by other creatures. The seeds are eaten by both small and large alike. How many times have we walked through the woods, picked up seemingly good acorns, only to later find a caterpillar in them? Yes, insects feed on the seeds too! Most often when we in Alabama think of acorns and nuts, we think of deer, turkey, and squirrels. Squirrels need large trees to survive. Squirrels live off seed sources from hickories, oaks, and pines. Deer and turkey are different. They require a variety of habitats. They like both field and forest. During the fall, acorns and nuts provide the needed fat in their diets to help see them through the lean days of winter. Humans can also consume acorns, but they are not as tasty as your cultivated pecans. The meat inside the shell contains higher levels of tannic acid than what we are accustomed. Indians used to collect acorns from white and chestnut oaks along with American chestnuts, black walnut, and wild pecan as a food source for the long winter months. As a side note; within the white oak family (oaks that produce white lumber) the acorns mature in one year, while those in the red oak family (pink lumber) take two years to produce mature acorns. Also, white oak family acorns tend to be larger than the red oak acorns.
Fall is my favorite season of the year. Cool Canadian air, leaves changing on the hillsides, and college football. For me, it all began this weekend with a single plink on my roof.
Andrew J. Baril of the Alabama Cooperative Extension System, C. Beaty Hanna Horticulture & Environmental Center, which is based at the Birmingham Botanical Gardens.
You see them evey year around this time, those pumpkins, squashes, and gourds with bumpy or warty exteriors in shades of green, yellow, orange, and white. Did you ever wonder how they got that way? Well I did, and I've looked into the matter, making some interesting findings to report.
Believe it or not, pumpkins are naturally warty. It was only through years of selective breeding that the smooth-hulled forms we know today came about; as this is the form that most appealed to consumers and thus proved most marketable. Some consumers value the bizarre aesthetic of bumpy pumpkins and gourds however, and so some plant breeders have worked to bring the bumps back. The trouble is, pumpkins in their naturally bumpy form aren't usually uniform in the spread and arrangement of their bumps, and so bumpy cultivars must be crossed repeatedly with one another to enhance their bumpiness into a more regular symmetry. According to Roy Pearman, director of sales and marketing for Siegers Seed Company in Holland, Michigan, it takes at least 10 generations of cross-breeding to produce a pumpkin that's adequately warty. Siegers markets a number of extra-warty pumpkin varieties under its Super Freak label, including 'Gargoyle', 'Knucklehead', and 'Goosebumps'.
Selective breeding isn't the only thing that produces bumpy pumpkins. Those plants afflicted with viral diseases such as cucumber mosaic virus, papaya ring spot virus, squash mosaic virus and zucchini yellow mosaic virus can have their normally smooth fruit transformed into bumpy orbs. These diseases also manifest in stunted vine and leaf growth, plus the namesake light and dark patches on leaf surfaces. These diseases are spread by the feeding of aphids, which transfer the viruses from infected plants to healthy ones. If you don't know whether the pumpkins you're growing are supposed to be naturally bumpy or if you're dealing with a viral infection, the bumps produced as a result of a virus appear to be emerging from the pumpkin's shell while those that occur naturally appear to be resting on the surface.
Mosaic viruses can actually be artificially induced in healthy, smooth-hulled pumpkins to achieve an instant bumpy effect. This practice isn't common, but viruses have found their uses in various other horticultural outlets. The Tulip breaking virus has been used by tulip growers for centuries to produce tulips with multi-colored petals. Tulips normally have petals in just one color, but when their bulbs are infected with Tulip breaking virus, their flowers grow to have stripes and streaks of multiple colors. Some citrus trees have also been artificially dwarfed through forced viral infection, resulting in smaller plants that are easier to harvest.
Back on the subject of pumpkins, squashes, and gourds of the highly textured sort, we have one more pressing question to answer. Can you eat them? For pumpkins and squashes, the answer is yes. The bumpy ornamental varieties only differ from their smooth counterparts in appearance, and are prepared and cooked just the same. Ornamental gourds on the other hand are inedible. You can tell a gourd from a squash by the thickness of the rind. Squashes have thin, soft skin, while gourds thick, hard rinds and a bitter, unpleasant taste. Always be sure to check the exterior skin texture before purchasing squash to eat.
Mitchell Vaughan, Auburn University Department or Horticulture and Extension Graduate Student, Fall 2016
Fall is upon us once again. Although it may not feel quite fall-like to us, deciduous trees and shrubs are starting to reflect the change. Forests throughout the state are already emblazoned with shades or red, yellow, and orange, with more plants transitioning all the time. But some observant individuals may have noticed the fall flush is a bit more ephemeral now compared to years past, with some trees shedding their leaves practically the same instant they change color. What's the cause of these short-lived displays? Is the lack of rainfall in our area to blame? To answer these questions and others, we'll need to take a trip back to middle school biology class and examine the science of why leaves change color in fall.
Deciduous trees and shrubs begin their annual growth in spring, when days become long enough and temperatures become warm enough to support the emergence of overwintering buds into new stems. This growth is typically completed by late June for most trees in the Northern Hemisphere. At this time, trees also begin to set next year's buds, which won't open themselves until they experience the chill of winter followed by the warmth of spring. Once this year's leaves are expanded and next year's buds are set, the tree will begin to manufacture carbohydrates through photosynthesis and store them to support next year's growth.
In late summer or early fall, days become shorter and nights longer. Deciduous trees and shrubs, like most plants, are very sensitive to night length. Once a certain threshold is reached and nights become long enough, these plants respond by forming what's known as an "abscission layer" where the leaves connect with the stems. This corky layer blocks the passage of material into and out of the leaves, including the green pigment chlorophyll. In the absence of chlorophyll, two new pigments become visible, the yellow pigments known as xanthophylls and the orange pigments called carotenoids. These are always present in leaves throughout the growing season, but are normally masked by the green of chlorophyll. Because these pigments are always present in leaves, yellows and golds tend to be fairly constant from year to year. One other group of pigments, the anthocyanins responsible for red and purple fall colors, are manufactured during fall from carbohydrates stored in leaves. These alone are not typically present during the growing season. The amount of these pigments produced depends on the amount of carbohydrates stored in leaves, and so the intensity of reds and purples is more variable in a given year.
Eventually, the abscission layer will thicken and the leaves will drop.
A number of environmental factors impact the intensity and duration of fall colors. Lots of sunlight and low temperatures after the time the abscission layer forms cause the chlorophyll to be destroyed more rapidly, resulting in earlier fall colors. Cool night temperatures combined with abundant sunlight promote the formation of more anthocyanins, and thus more intense reds and purples. Freezing conditions halt the production of anthocyanins, so early frost means an early end to colorful foliage. A growing season with ample moisture that is followed by a dry, cool, sunny fall with warm days and cool (but frostless) nights provides the best weather conditions for development of the brightest fall colors. Lack of wind and rain in the fall prolongs the display; wind or heavy rain may cause the leaves to be lost before they develop their full color potential.
Drought, in particular, can have a severe impact on fall colors. Drought conditions can slow the process of color change, and lead to less colorful, muted displays. Drought stress during the growing season can also sometimes trigger the early formation of the abscission layer, and leaves may drop before they even have a chance to develop fall coloration. Lack of moisture should have less of an impact on yellows and oranges than reds and purples, but these leaves also won't be hanging around too long.
So there you have it. Enjoy the splash of colors while you can, because like fall in the South, it won't last long.
Did you know that about one third of our garden fruits and vegetables, and the flower seeds we harvest from our gardens, are the result of bees? Having a garden "friendly" for bees' means it is also friendly for many other beneficial forms of wildlife, such as butterflies and hummingbirds.
Of the 2,500 or more species of bees in the U.S., nearly all are gentle and won't sting you unless they feel threatened or provoked. This is not their goal. Nor is it to pollinate our flowers for our use. They don't chew up our flowers either, as some people believe. Rather, they are merely trying to find food for themselves and their young, or to gather home building supplies. In doing so, they end up pollinating our flowers, fruit trees, and shrubs.
The most common bees, especially early in the season, are the honeybees. As they hibernate for the winter, they must make and store plenty of honey. Bumblebees appear later in the season. Male bumblebees die after mating, the workers die at the end of the season, and so only the females survive. They hibernate in holes in the ground, old mouse nests, and similar places.
The worker honeybee collects pollen on brushy hairs, storing it in leg pockets. Worker bumblebees have a long proboscis to collect nectar, something other bees can't do. The other common bees are the solitary ones (Adrenidae family) that don't live in colonies.
Bees are attracted to flowers that are colorful or contrast well with their background, or have an ultraviolet coloration that serves as a nectar guide. This is especially true in the case of red flowers, which bees don't see unless they contain some ultraviolet light, which we usually don't see.
Purple and blue are bees' favorite colors, followed by yellow and orange. Many newer cultivars of flowers, especially annuals that have been highly bred, are deceptive to bees. Even though they may have attractive colors, they lack the pollen and nectar that bees like because these traits have been bred out.
In addition to flowers, bees need a source of water if one is not nearby. A small pond, puddle, birdbath, or even dripping faucet usually fulfills this need.
Bees need protection from predators, a place to call home. Many bees live in old or dead wood, often in tunnels created by wood-boring beetles. This is true for most bees in the leafcutter bee family (Megachilidae). If you spot some elliptical holes in leaves on garden plants, they are likely from these bees gathering leaf pieces that they use for homes for their young.
So, think of these bees before cutting down dead trees, or even limbs. Dead trees will also be attractive to several species of woodpeckers. In addition, many bees live in holes in the ground, so leave some bare ground for them in an out-of-your-way part of your yard or garden.
The final point crucial to bee survival is to avoid using pesticides that will harm them. Either avoid using pesticides, or if this is not possible, use them after dark when bees are not active. And be sure to read all label directions. The label will tell you if the material is toxic to bees and methods of protecting them from the product. Remember that you usually have other, less toxic choices, so always choose the least toxic product for the pest management job.
Dr. Leonard Perry, University of Vermont Horticulturist was used as resource for this article.
In my opinion, there are two types of gardeners: those that already are, and those that want to be. I firmly believe that anyone can garden. It’s amazing that some people contend they can’t, for one reason or another. So finding a short unofficial study of reasons why people don’t garden, I decided to share with gardeners and potential gardeners alike. And in the process, convince a few folks there are many ways to garden, one of which will work for them. (photo credit: Adrienne Bourland)
1. I kill everything I touch2. I’m under a doctor’s care for [fill in blank]3. I’m afraid gardening will hurt my [fill in blank]4. I don’t have any place to plant a garden5. I can’t stand the heat6. I can’t stand the cold7. I can’t stand8. I don’t like to sweat/get dirty/mess up my nails9. I don’t have the time10. Why should I when there’s a store for that?
A friend confessed “I can kill an African violet just by looking at it”. Since she is an accomplished gardener, my glee in discovering she isn’t perfect was tempered by the realization that some plants just don’t work for me either. So get over it, accept that we all have affinities for certain people, pets, and plants, and keep trying. The plantsman J.C. Raulston put it this way – “You’re not stretching yourself as a gardener if you’re not killing plants.” Well, I’m certainly in the “stretched” category, and honestly that’s usually how we learn – by our mistakes rather than successes.
Physical limitations are a fact of life, and not only with older citizens. From small children with less strength and attention span to seniors whose joints “talk” to them and who find bending over not an option, there is a way to garden. Gardens are used for mental and physical therapy, including cancer patients, those with dementia, limited sight, those trying to assimilate into our local culture and environment. Gardening speaks a universal language.
Do check with your physician before undertaking any new activity but be aware that gardening can be gentle as well as intense. There are calories burned and muscles stretched associated with almost any gardening activity, and if done correctly (we do know how to pick up items using our legs instead of our backs), can benefit our overall health.
No place to plant a garden? Houseplants qualify, as do container gardens, raised bed gardens, windowsill gardens, bathtub gardens, back porch and patio gardens, and a college student’s bookcase garden. The concept that only an in-ground plot of flowers, vegetables, or whatever is a “garden” is not only outdated, but an insult to those who garden no matter where and to what degree. I’ve seen some fabulous gardens on the 4th floor of high-rise apartments in the most urban of environments. I wouldn’t begin to dismiss those passionate folks as anything other than gardening “soilmates.”
Weather conditions certainly impact our ability to garden but if plants can handle hot, cold, dry, wet and survive, certainly we can adjust our gardening practices to accommodate a variety of conditions. That includes wearing appropriate clothing, such as gloves. Not only will they keep hands clean, they’ll protect against thorny plants (think roses) that need tending. From head to toe, hats to boots, garden suppliers offer both functional and whimsical items for use in our gardens.
Naturally the bigger the garden, we’d expect to spend relatively more time tending to it. So, if you’re in the “wanna be a gardener” group, keep it simple and start small. Pots or containers can be easier to handle but keep in mind that plants will need monitoring. Everything that makes plants grow is confined to what’s available within the width and depth of its growing environment, i.e. pot.
Yes, there’s a store selling the flower or vegetable, but you don’t get the same rush as growing it yourself! Nor the freshness, nor control of what was sprayed on the plant. There’s undeniable satisfaction in the planting, nurturing, and enjoyment associated with “I grew that!”
So … why don’t you garden?
Written by Sallie Lee of the Alabama Cooperative Extension System (ACES). She is housed at the C. Beaty Hanna Horticultural and Environmental Center, which is based at the Birmingham Botanical Gardens. Email questions to Sallie at firstname.lastname@example.org or call 205-879-6964 x11. Like us on Facebook. Follow us on Twitter. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University), is an equal opportunity educator and employer. Everyone is welcome!
We're all (unfortunately) familiar with the red imported fire ants that have become so prolific in lawns across the southern United States. These were introduced from South America early last century through our own Mobile, Alabama on cargo ships. We might not be aware of the billions of dollars these ants cost anually in agricultural damage, pest control costs, and hospital bills from treating their painful and even potentially deadly stings. Still less familiar to most people are one of the fire ants' natural enemies, the phorid flies, otherwise known as ant-decapitating flies.
These flies, also native to South America, belong to the genus Pseudacteon, and are parasitoids of fire ants. Unlike true parasites which depend on their hosts for survival, parasitoids eventually sterilize or kill their hosts. As the name ant-decapitating fly suggests, the host insect's death might be seem as brutal.
Female phorid flies, in an ironic twist, are attracted by the smell of the ants' alarm pheromones, a chemical substance which the ants themselves release to warn their fellow ants of impending danger. Once she has a target in site, the female fly deposits an egg inside the ant's thorax. The egg then hatches and the newly hatched larvae migrates to the ant's head, where it feeds on its host's bodily fluids and later its brain.
Eventually, the fly larvae releases an enzyme which causes the ant's head to fall off. The fly larvae completes its development within the decapitated ant head, until it emerges like something out of a horror movie and begins the process anew. ..............................
Alabama is home to dozens of species of native phorid flies, most of which are believed to be parasitoids of other insect species. This includes phorid flies in the genus Apocephalus, which are parasitoids of our native carpenter ants, and which grow much larger than their tropical cousins. This is because the host carpenter ants themselves are much larger (and have much larger heads) than fire ants, meaning a larger food source for larger flies.
Since we have these ant-decapitating flies right here in the United States, you may be wondering why we still have so many fire ants around. That's because these phorid flies are very host-specific in their feeding. The native phorid flies here in the US attack native ant species, but very rarely touch imported ant species. As is often the case with imported (and many times invasive) organisms, we need to also import the accompanying parasitoids and other pests that keep their populations low in their native homeland.
The good news is, pest control companies and entomologists alike are doing just that. Since 1997, South American phorid flies have been introduced across the Southeast, from Texas to Mobile. Preliminary results from these introductions point to a 10 to 20 percent drop in invasive fire ant populations.
Look forward to many decapitated fire ants coming soon to a lawn near you!
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