This is a collection about horticulture.

Problems with Ornamental Pear Trees November 20, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 5:29 pm
pear tree

Ornamental pear tree with cracking and flaking bark.

Pear trees in our area have a problem.  Cracking, plating, and flaking bark has been reported in many ornamental or flowering pears across the region.  What caused this problems and what can you do about it? (more…)


Fall Garden Clean-up November 18, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 9:23 pm

The presence of frost usually means that your vegetable garden is either limping toward the finish line or has completed production for the year. Fall is the pgarden cleanuperfect time to clean up the vegetable garden and its tools to prepare them for next year.

There are a few more tasks to complete before you put your gardening tools away for the winter. Before you perform the actual clean-up of the garden, make notes about the year. Record the garden layout, cultivars that worked (or didn’t), and pests or diseases you encountered this past year. This will help you next spring when it is time to plan the garden and help you to remember what vegetables were in which location for your crop rotation schedule. The goal is to have a 3 year crop rotation plan. This is where vegetables from the same plant family are rotated around different locations within the garden. The objective is to avoid placing those plant families in one particular location for 3 years.

The actual clean-up of the garden is the next step. Elimination of garden debris, like dead plant material, fruit ‘mummies,’ weeds, and rotting vegetables, can help to reduce disease, weed, and insect problems next year. Remove and discard disease or insect infested plant material, but do not compost. Compost piles do not reach high enough temperatures to kill all pathogens, like fungal spores and bacteria. Discarding or burning the infected plant material will remove the pathogens that could potentially infect next years’ crops. Removal of weeds with mature seed heads will not only improve the appearance of the garden, but also help remove the seed source for potential weeds in next years’ garden.

Adding organic matter can help improve soil composition. Incorporating residues from healthy plants can act as a great source of organic matter, which can improve the texture of the soil. These healthy plants can either be turned or tilled into the soil or tossed into the compost pile. Organic mulches that were used in the garden, like straw, grass clippings, or even newspaper, can also be tilled into the soil. Tree leaves are another great source for organic matter for the garden. Leaves that are picked up with the lawn mower will break down faster once they are worked into the soil because they are chopped into smaller pieces.

Cages and trellises also need some clean up in the fall. Support structures, like tomato cages or trellises, should be pulled out of the ground, cleaned up, and placed in storage for winter. If you have had disease issues in the past, like blight in tomatoes, now is also an excellent time to disinfect the cages or trellises to keep them from infecting new plants next year. A 10% bleach solution, alcohol wipes, rubbing alcohol, or even ready-to-use bleach wipes can be used to disinfect the cages prior to winter storage.

Speaking about putting your garden tools away for winter…it’s time for some end-of-the-year tool maintenance. Digging tools, like shovels, hoes, pitchforks, and garden rakes, should have excess soil removed from them. Any rust that is present can be removed using a wire brush and a little bit of elbow grease or an electric drill with a wire brush or sanding attachment. After rust is removed, renew or sharpen the edges and points with a mill file or grinding wheel. For winter storage, apply a light coating of oil. Tools can even be stored in a 5 gallon bucket filled with sand and oil. Inspect the handles of your tools at the end of the season for cracks or splinters. Replace the handles if necessary. If the wooden handles are in good condition, they can be sanded and oiled at least once a year. Use a fine grade sand paper to smooth the surface. Remove any dust and rub linseed oil into the handle and allow it to soak in. Keep applying until the oil doesn’t absorb any more. Wait a half hour, and dry off any oil remaining on the surface.

Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.


Colorful Canopies: Fall Foliage in Nebraska November 5, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 6:02 pm
Beautiful Fall Color on Campus by Tim Harwick

Beautiful Fall Color on Campus by Tim Harwick

Cooler nights, apples, pumpkin flavored everything, and football can only signal one thing, fall is here. This year has been a wonderful one to see fall color in Nebraska’s landscape. What exactly causes this fall color and how can we see it every year? The answer is more scientific than we think.

The science behind leaves is as complex as it is interesting. The colors that we see in the leaf comes from cells called pigments. The green pigments that we see are called chlorophyll. Some of the other pigments that offer the other fall colors are present all year long, they are just covered up by the green chlorophyll. When the days become shorter and cooler, the production of chlorophyll slows down and eventually stops. When the green color disappears, the other hidden pigments are now able to show off their full beauty. Carotene and xanthophyll are the yellow pigments that are produced in the foliage all year long, but aren’t present until the chlorophyll disappears. The anthocyanins are responsible for the red and purple pigments. The anthocyanin production increases with the increased levels of sugars in the leaves.

Often Jack Frost gets all the credit for the fall display, but actually he has little to do with it. Fall color is controlled by the plant’s genetics and the environment. The weather conditions such as temperature, moisture, rain, wind and the availability of sunlight impact the quality of the fall color. Clear days, cool nights, and dry conditions provide the best fall color. The two-tone effect that often happens in green ash can be explained by the outer branches being exposed to sunlight, while the inner branches are shaded.   Heavy winds, rainfall, freezing temperatures can kill the leaf tissue and shorten the fall color display.

Often we only think of fall color in our deciduous trees, but evergreen needles change color in the fall too. It is a normal occurrence called natural needle drop. The older interior needles of pine and spruce are turning yellow and eventually drop from the tree. The older needles that are lost are usually located closer to the inside of the tree or trunk. Factors that increase the stress on an evergreen can intensify the autumn needle drop. These stress factors can include drought, herbicide injury, root damage, or insect or disease damage.

Like many living things, evergreen needles also have a lifespan. Pine trees hold their needles for 2-3 or more years. Spruce trees hold their needles longer than pines, usually around 5-7 years. After the needles have lived their lifespan, they fall from the tree. Some trees, like the white pine, make it easy to see the needle drop.

Looking for a plant that will provide fall color? If you are looking for an orange color, sugar maple, serviceberry, some crabapples, and oakleaf hydrangea might be worth a try. White, red, and scarlet oaks, flowering pears, Ohio buckeye, red maple, and the burning bush provide red color. Yellow fall foliage plants can include the Kentucky coffeetree, Norway maple, silver maple, cottonwood, elm, and quaking aspen. Purple is a little more difficult to find, but the gray dogwood and some viburnum species can provide the splash of color that you are looking for. Ash is one tree that does offer good fall color, but it isn’t recommended for our area due to the looming infestation of the Emerald Ash borer in our state.

Embrace fall. Select plant material that will offer multiple seasons of interest then kick back with a pumpkin latte and enjoy the natural display of beauty.

Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.


A Mountain or a Molehill?? October 25, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 8:30 am
How a molehill is made. Photo courtesy

How a molehill is made. Photo courtesy

We have all heard the saying, “Don’t make a mountain out of a molehill.” That can be difficult if we don’t even know what a molehill looks like. Knowing more about this pest can help you identify the damage and keep them from making molehills in your yard.

Moles are interesting critters. For starters, they ‘swim’ through the soil with their front feet and have very poor eyesight. They live in secluded, underground burrows and rarely come to the surface. There is not ‘off season’ for the mole because they do not hibernate and are active all season of the year.   Moles live alone and create an extensive network of burrows and tunnels. Sometimes several can be trapped in the same location, but that doesn’t mean that they are all living in the same burrow. Networks of runways can be made independently and can occasionally join. One mole can feel as though there are several due to the amount of damage the runways cause.

The diet of the mole is also often misunderstood. If you look at the teeth of a mole, they look more like those of carnivorous, meat eating animals than rodents. Often, the mole is blamed for damage to plant roots and tubers, but rodents are the real culprits. The mole’s diet consists mainly of worms, grubs, and insects it finds in the soil. Around here, a majority of the mole’s diet is actually earthworms, not grubs. If you have moles, it doesn’t necessarily mean you have grubs and need to treat with an insecticide. Treat for grubs if you have had an issue in the past, if threshold limits are exceeded, or if the turf pulls back like a carpet, not just because you have moles. There is not a product labeled on the market for control of earthworms, so you are out of luck there too.



Moles are a blessing and a curse. The good news is that they remove many troublesome insects from lawns and gardens. The damage left behind by the moles feeding is the worst part. Their burrowing can damage lawns and parks, destroy flower beds, tear up grass roots, and create havoc in small garden plots. Properly identifying the pest is key to knowing if you are making the right move for controlling them. Moles will leave 2-24” volcano-shaped hills of dirt that are pushed up from deep in the tunnels. The entrance hold to the tunnel will not be visible in the hill. The surface tunnels just under the turf are also a dead giveaway.

Controlling moles can turn out to be the tricky part. There aren’t any repellants that can be sprinkled on the lawn or in the run that are effective for repelling moles. The frightening devices like the electronic, magnetic, or vibration producing devices are not effective either. Juicy fruit gum, bottles buried in the ground, or pinwheels are equally ineffective.

The good news is there are a few other methods that have been proven to be effective. Exclusion is one method. Hardware cloth buried at least 12 inches deep and bent out at 90 degrees can help keep moles out of small areas. Toxicants can be effective if you select the right one. Poison grains, peanuts, or pellets are ineffective because the mole doesn’t eat those foods. The baits that are shaped like earthworms will give you best results. When the mole finds this bait in the run, he thinks he has just found his favorite food and bites down. Be sure to read and follow label instructions on any pesticides that are used. Traps are another method to try. If used properly they can give good results, but this can be trickier than it seems. The traps need to be placed in an active run. To ensure they will fire properly, you might consider dry firing the trap prior to setting it for the mole. This will help to make sure the moving parts of the trap will move freely to capture the critter. Also consider covering the area where the trap is located to make sure there isn’t any sunlight penetrating into the run.

Don’t make a mountain out of a molehill, or better yet, don’t have a molehill in your yard at all. Showing a little patience and using the right control method will help to keep your lawn and garden intact and mole-free.

Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.

A Mountain or a Molehill (PDF)


Arrrgggg…. Pirate Bugs & Hackberry Psyllids October 4, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 8:30 am

We are all trying to make the most of these last warm fall days. While enjoying the last little bit of warm weather, tiny terrors seem to be everywhere. Find out what the little insects are up to and how you can keep from going nuts.

Minute Pirate Bug- the tiny biter

Minute Pirate Bug- the tiny biter

The minute pirate bug is one such insect that is out at this time of year. Orius insidiosus, also known as the insidious flower bug. It is a predatory insect in the order Hemiptera. This tiny oval shaped insect is 1/8 of an inch long and black with whitish markings on their wings. The pirate bug larvae and adults are very effective predators that feed on thrips, mites, aphids, small caterpillars, and insect eggs. In the summer months, crop fields and landscapes are full of pirate bugs feeding on insects, but in late summer and fall they start biting humans. It isn’t their fault that they bite humans, they just mistake us for very large prey. The bite of this insect is surprisingly painful for their size. They use their sucking mouthparts to puncture and break the skin. They do not feed on blood, inject venom, or transmit disease. As with any insect, everyone reacts differently to their bites. Reactions can range from none to having the area swell up like a mosquito bite or turn into a hard red bump.

The downside to these tiny terrors is that it is not practical to control them. Mainly because a majority of the year they are beneficial predators and the people biting is later in the season and is temporary. If you are prone to being bit, there are a couple of options to try. Wearing dark clothing on warm days when the pirate bugs are active may help. Keeping covered with long sleeve and pants will also help to keep them from coming in contact with skin. Insect repellants might not be all that effective against the pirate bug, but if you are a pirate bug magnet it might be worth a try.

Hackberry galls caused by psyllids

Hackberry galls caused by psyllids

Another tiny terror that will soon be upon us is the hackberry psyllid. If you have a hackberry tree in your yard or neighborhood you are already well acquainted with this insect, maybe just not by its formal name. These tiny 1/10th of an inch insects are attracted to light and are small enough to pass through a window screen. Hackberry psyllids are the insects that make the nipple galls, or bumps, that are common on the underside of the hackberry leaves. The eggs of this insect are laid on the leaf. In response, the leaf forms a gall, or bump, around the immature insect to protect the it until it is mature and emerges from the gall. Once they emerge in the fall, they look for cracks or crevices to squeeze into so they can hibernate without freezing to death. Normally they overwinter under the bark of trees, but they often find their way into homes. Once inside, they often die due to the low humidity. The insects are not harmful to people, pets, or any home furnishings. They are just a nuisance pest. Once it gets cold outside their numbers will decrease and they will begin to hibernate.

Control of these insects can also be tricky. One reason is because of the way the insect develops inside of a gall. For a majority of their life, the psyllid is encased inside of a gall and is protected from insecticide sprays applied to the foliage. Once the adults emerge in the fall it is too late to control them by spraying the trees. The trees can be sprayed in the spring to kill the newly hatched nymphs, but timing the applications can be very difficult. Egg laying happens over a several week period which could potentially mean several insecticide applications. It can also be impractical and not cost effective to spray large trees numerous times. Soil drenches of insecticides could prove to be an option for those who are extremely desperate for some relief, but is not usually recommended. Spraying in or around the home is usually not recommended because of the lengthy emergence of the adults from the galls. Unfortunately the best thing to do is keep the windows shut until the temperatures drop low enough to stop their activity. Once inside the home, the vacuum cleaner is the best weapon the suck up the intruders.

Don’t let the tiny terrors ruin what is left of the nice weather. With a little help, and proper identification, you can stay sane and not become the next mistaken prey of the pirate bug.

Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.


The War on Turf Weeds October 1, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 8:10 am

The saying, “Timing is everything,” could never be more true. Proper timing of herbicide applications can not only save you the frustration of having a lawn full of weeds, but it can also lead to better control of those pesky plants. Properly identifying the weed and knowing its growth habit is helpful in knowing if or when is the best time to apply herbicides for the best results.

Henbit- a winter annual

Henbit- a winter annual

Knowing the type of plant you are dealing with is crucial in its control. Annual weeds require a little different approach than perennial weeds. Annual weeds are those that sprout, grow, set seed, and die all within a year. Annual weeds fall into one of three categories. There are the spring annuals, like crabgrass; summer annuals, like knotweed or sandbur; and winter annuals, like henbit. Each one has a different set of temperatures and requirements it needs in order to germinate. Perennial weeds can grow and set seed in a year, but they continue to come up year after year, like clover and ground ivy.

There are several options for control of weeds. Knowing the plants’ life cycle and when it germinates will help in the timing of herbicide applications or if hand pulling is needed. Preemergence herbicides keep the seeds from germinating, or sprouting, which keeps the weeds from becoming a problem, and are usually used to control annual weeds. Once the seeds have germinated, the preemergence herbicides are not effective at controlling the growing weeds. Postemergence controls will do a much better job of controlling the weeds once they have germinated. Perennial weeds come up every year from the crown of the plant. This makes preemergence herbicides not effective in controlling these weeds as they only have an effect on seeds. Postemergence herbicides or hand removal are two common methods of control. Hand pulling or digging the weed may require a little elbow grease, but it is an effective method of control if you get the whole root system and have the time.

Timing of post emergent control is just as important as the timing of preemergence herbicide. Early season control of many weeds can give you better efficacy. As in the case with some perennial weeds, summer applications of broadleaf weed killers might just burn back, or brown, the foliage for a little while, only to have it regrow new leaves a little while later. Comparatively, later season applications to annual weeds might make you feel better, but it might only kill the plant a month earlier than it normally would have died due to frost.

There are some products that can be affected by the heat. Some broadleaf weed killers, like 2, 4-D, in the heat can volatize, or switch from a liquid to a gas. When this happens, the product that was applied to the weed can drift over and damage nearby sensitive plant material. The most common indicators in the garden are peppers, grapes, potatoes, redbud, and tomatoes. Symptoms can be leaf yellowing, distortion, and cupping upward of the leaf. Sometimes the herbicides can also cause a twisting, curly-q appearance to stems and petioles, leaf stems. To prevent herbicide damage, avoid applying herbicides for weed control during the hottest months to sidestep injury to non-target plants.

Proper timing, identification, and the right product/method are the secrets for good weed control. With a little luck, your weeds might have met their match.

 Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.


Got Yellow Grass Instead of Bluegrass? August 24, 2015

Filed under: Uncategorized — Elizabeth Killinger @ 8:30 am
Yellow color in a bluegrass lawn.

Yellow color in a bluegrass lawn.

Timely rains this year may have kept many from running their irrigation systems, but they could have also done much more than that. Moisture has kept many lawns from going dormant and heavy rains are most likely the reason for many the weeds in the turf and in some cases, its yellow appearance.

Yellow colored Kentucky bluegrass has been spotted all around the region.   While we don’t know the exact cause of the yellow lawns, there are several factors that are known. The symptoms appear to only be affecting some cultivars of Kentucky bluegrass. It has not been seen in tall fescue or perennial ryegrass. The symptoms mainly appear only on the upper, young leaves. This discriminating coloration means that it probably isn’t a deficiency of nitrogen. Nutrients like nitrogen are mobile in the plant; if one leaf is affected, they will all be affected. Other nutrients like iron might be to blame as it isn’t as mobile in the plant, which can lead to spotty symptoms. On the turf that has been examined, there isn’t a notable lesion or spot on the leaf, which rules out many diseases and fungal infections.

The weather we have had this season might be playing a role in the yellow streak. The symptoms are most often seen in lawns that are mostly irrigated or received more than adequate amounts of rain. They also happen when the soil temperatures are at their seasonal highs during wet summers. There can be some similar yellowing symptoms in the spring, but they are attributed to denitrification, or loss of nitrogen, in the soil.

What can a person do? You will be happy to know that this sickly color only affects the visual appeal of the Kentucky bluegrass. It doesn’t seem to have any long term impacts on the overall health of the plant. No need to apply a fungicide, insecticide, or fertilizers with less than 0.5 pounds of nitrogen per 1,000 sq ft. Reducing irrigation for the short term should help with this coloration issue. If you wanted to try to green up your turf, you could try a low rate application of iron. This could give you back your green color, without the use of nitrogen fertilizer, which isn’t recommended in August. Mowing could also remove a majority of the discolored younger foliage which is higher up in the canopy.

Some longer term solutions might need to be considered if this turns out to be an annual occurrence. The main goal is going to include increasing drainage and reducing compaction. Core aeration is one way to increase drainage to lawns that are compacted, on heavy clay, or have heavy traffic. Another longer term option could include overseeding with a different cultivar of Kentucky bluegrass or possibly changing turfgrasses altogether. To get the best of both worlds, you can try both aeration and overseeding. Take advantage of the holes caused by core aeration and overseed at the same time. The rule of thumb is that for each week grasses are seeded before Labor Day, development is speeded by two weeks. The optimal window to seed cool-season turfgrasses is August 15 to September 15. Thin stands of Kentucky bluegrass should be overseeded with improved cultivars at .75 to 1 pound of seed per 1,000 square foot. If you are overseeding a tall fescue lawn, use a blend of improved turf-type tall fescue cultivars at a rate of 4 to 6 pounds of seed per 1,000 square feet. Ensure the seed has good seed to soil contact and irrigate frequently to for the best germination.

If your lawn has a yellow streak, don’t worry. A little time and a lot of patience will yield a greener appearing lawn.


Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at, her blog at, or HuskerHort on Facebook and Twitter.



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