42

In The Backyard

Horticulture columns and tips done on a timely basis

May 26, 2011

Foundation Sprays

If you have been following a foundation spray program all year, keep it up. If you haven't been, it is probably time to start. The foundation spray program is your first line of defense against nuisance pests in the house. It cuts down on crickets, millipedes, spiders, ants, and many others that find their way inside. And, with the crickets singing, it's only a matter of time before they find their way into your abode.

To accomplish a foundation spray, you would select a material such as permethrin or bifenthrin to begin with. Then spray the foundation and the adjacent foot or two of soil or plant material with the spray mixture. Both these products are cleared on most types of plants. Foundation treatments should be applied every 7-15 days depending on the temperatures. The materials break down quicker in hot weather.

Foundation treatments won't prevent everything from getting in the house, and they certainly won't kill things already in the house. For insects already in the house, you have a few options. The first is mechanical control. This is fancy language for something like a flyswatter, shoe, vacuum cleaner, flypaper, or glue boards. The next is chemical control. This basically means aerosol cans inside the house. The most common ones are for flying insects or ants, although many of the flying insect killers now have permethrin in them and can last quite a while.

Posted by John Fulton at 11:07 AM | Permalink |

May 26, 2011

Leaf Diseases Accelerate

As mentioned last week, fungal leaf diseases were present. They are now making their presence felt with a vengeance. These diseases infected trees and shrubs earlier, and they have continued to develop rapidly. Adding insult to injury, we had the extremely high winds affecting the tender leaf tissue, especially on maple trees. Some trees are now to the point of being, well, leafless.

Anthracnose is the number one fungal disease of good quality shade trees, and apple scab is starting to hit apples and crabapples. To give a brief overview, these diseases are preventable but not curable. They are seldom life threatening to the tree or shrub, but they can make things look rather unsightly. Many shade trees losing a large percentage of their leaves will often set another set of leaves within four to six weeks. Apples and crabapples are less likely to set another set of leaves, but it sometimes happens.

Anthracnose has different stages depending on the time of infection. There is a bud stage, where buds are killed as they begin to open. Next is a leaf stage, which affects only leaves. This stage is the one we are commonly seeing, and it infects leaves and gradually consumes the leaf. And the other stage is the twig stage which affects smaller twigs on trees and shrubs. This is one reason why sycamore trees tend to have so many small branches break. The infection leaves a brittle scar on the branch which makes it susceptible to breakage. There is actually a specific anthracnose disease for each shade tree. This means sycamore anthracnose, maple anthracnose, and so on.

As I mentioned, once infection has occurred it can't be cured. The prevention part needs to begin with a regular spray program similar to production apples. This means starting when the leaves are just out of the bud in the early spring. The same kind of timing applies to ornamental trees. The main harm caused is the loss of food produced by the lost leaves, and the loss of energy to set another set of leaves. Fertilizer application at the lawn rate, to supply a pound of nitrogen per 1,000 square foot broadcast, will help the tree as much as anything.

Posted by John Fulton at 11:06 AM | Permalink |

May 26, 2011

Tomato Care

With the widely fluctuating amounts of rainfall, blossom end rot is definitely a possibility. It has even started on some container grown tomatoes. The best solution is to mulch tomato plants to help even out the moisture supply, and help keep the roots cooler. This problem is caused by uneven calcium amounts in the plant. Addition of lime when you see the problem usually isn't as effective as evening out the moisture flow for the plant by mulching. Any material will do (grass clippings, straw, commercial mulch, etc.) with two inches being adequate and four inches being better. You may have to compensate with a small amount (emphasis on small) if you use items which decompose quickly – such as grass clippings.

Posted by John Fulton at 11:05 AM | Permalink |

May 16, 2011

Swarms

With some warmer weather comes the swarms of insects that raise that perennial question of "Are they ants or termites?" Swarming time for both insects is about the same time, and they are really looking to start new colonies because they have outgrown their old ones. This is the reason for the winged insects, as the wings allow the ants or termites to cover larger areas to start their new colonies. The differences between ants and termites are several.

Let's start with the body color. Termites are always blackish in color, while ants may be black, red, brown, or other colors. If you have winged insects that are not black, you don't have termites.

Next look at the body shape. Ants have a constricted "waist" while termites don't have that classic "hour-glass" figure. Antennae and wings are the other two body parts to look at. Antennae on ants are elbowed, basically in an "L" shape, and those on termites are straight. Both ants and termites have two pair of wings, but those on termites will be of equal length while ants will have wings of different lengths on each side.

Looking through those entomology fact sheets also brings up a few important points in the event that you do have termites. First, don't assume that the house will fall in overnight. Take the time to get several bids from reputable companies for the treatment. Make sure you compare cost, service, and guarantees. Second, termites are pretty much a professional treatment job, unless you have an exposed foundation such as in a new construction project. Third, there are traditional treatments to kill the insects, and other treatments which render them incapable of reproducing. Drenches, pressure injection, and bait stations are all options. If ants are your problem, use of bait stations or baseboard sprays may help solve your problems. Many of the bait station programs will require a good week to ten days to be effective. Remember that damage done by ants, even carpenter ants, is not structurally damaging to your home. They simply make a nesting hole in wood rather than digest it.

If you have further questions on termites, or the do-it-yourself identification doesn't seem to work, by all means contact the Extension Office at 732-8289.

Posted by John Fulton at 3:09 PM | Permalink |

May 16, 2011

Spray Programs

For most of your fruit trees and also your crabapples, spray programs should have begun when the leaf buds started to open. According to the pest control handbook, sprays should continue on about a 10 day schedule until within 2 weeks of harvest for fruits, and until fruit set on crabapples. For the homeowner, a multipurpose fruit spray is the easiest product to use (it contains 2 insecticides and a fungicide). Just remember to avoid spraying insecticides on flowering plants because of toxicity to bees (like right now on apples.) You can substitute plain captan fungicide during flowering to continue your disease control.

Keep in mind that these types of sprays are preventative in nature. That means that you need to have the sprays in place before you have problems. Once problems appear, there is very little that can be done.

If you want more information on spray programs, feel free to stop by the office and pick up a copy of the "Home Fruit Pest Control" publication that is available at no charge. While the insecticides have changed, the timing has not.

Posted by John Fulton at 3:07 PM | Permalink |

May 9, 2011

Tree Leaf Diseases

With the cool, wet weather we have been experiencing it is only a matter of time before the fungal diseases make themselves widely apparent. These would include apple scab on apples and crabapples, as well as anthracnose on the good quality shade trees. Both diseases are present in their early state at this time.

To give a brief overview, these diseases are preventable but not curable. They are seldom life threatening to the tree or shrub, but they can make things look rather unsightly. Many shade trees losing a large percentage of their leaves will often set another set of leaves within four to six weeks. Apples and crabapples are less likely to set another set of leaves, but it sometimes happens.

Anthracnose has different stages depending on the time of infection. There is a bud stage, where buds are killed as they begin to open. Next is a leaf stage, which affects only leaves. This stage is the one we are commonly seeing, and it infects leaves and gradually consumes the leaf. And the other stage is the twig stage which affects smaller twigs on trees and shrubs. This is one reason why sycamore trees tend to have so many small branches break. The infection leaves a brittle scar on the branch which makes it susceptible to breakage. There is actually a specific anthracnose disease for each shade tree. This means sycamore anthracnose, maple anthracnose, and so on.

As I mentioned, once infection has occurred it can't be cured. The prevention part needs to begin with a regular spray program similar to production apples. This means starting when the leaves are just out of the bud in the early spring. The same kind of timing applies to ornamental trees. The main harm caused is the loss of food produced by the lost leaves, and the loss of energy to set another set of leaves. Fertilizer application at the lawn rate, to supply a pound of nitrogen per 1,000 square foot broadcast, will help the tree as much as anything.

Posted by John Fulton at 8:10 AM | Permalink |

May 6, 2011

Spruce Tree Woes

Many spruce trees, especially Colorado blue spruce, are not very well acclimated to our environment in Central Illinois. The altered growing conditions often weaken the tree over a period of time, making it more susceptible to other diseases and insects.

Rhizosphaera needle cast is one of the main diseases of spruce. Symptoms include a purple cast to needles, needle drop, and a tendency to start at the bottom of a tree and work upwards. One key to control is removing infected needles and cleaning pruning equipment between cuts. Chemical control is possible by protecting new growth with chlorothalonil fungicides such as Bravo or Daconil 2787 or manganese/zinc combinations such as Cleary's Protect T/O. These programs would probably have to be done for at least two years, and make sure to follow the recommendations on the product label.

Other diseases such as diplodia tip blight and cytosphora canker also affect spruce trees, and let's not forget spruce spider mites. Spruce spider mites have been active for a while, and will probably continue to be active with the cool weather we have had this spring. This insect damage shows up as mottled needles, and there is usually fine webbing present. Needles may also drop from the spruce spider mite. Control of the mite can be accomplished with insecticidal soap or an appropriate miticide.

Posted by John Fulton at 4:23 PM | Permalink |