Joe Eakes is overseeing a study on fertilizer evaluation, comparing Multicote, a new product, to two industry standards, Osmocote and Nutricote. He will be looking at growth data, plant quality, pot temperature and will monitor leachate. Another study of Dr. Eakes is on azaleas using Polyon, Osmocote and Nutricote. More nitrogen appears to yield better color and growth in some ornamental plants.

Ken Tilt and Rob Trawick brought trees and photographs to illustrate the importance of cyclic irrigation. The same amount of water was applied to trees in one, three or six applications daily. Trees which were irrigated three times a day did the best in this study; they grew significantly larger than their counterparts. There are many theories as to why this is the case. Perhaps fertilizer is used more efficiently. Perhaps it is because the plants are less stressed as they get water frequently, instead of just once. What Ken and Rob can say conclusively, though, is that cyclic irrigation is always superior to a once-daily regimen.

Their other study involves copper treatments in pots, specifically, whether copper can have a toxic effect on plants. SpinOut containers were used. These containers were painted with a copper hydroxide paint which is still potent after two years. RootRight containers have copper incorporated into the plastic, which lasts longer than the painted copper. Both treatments were used to keep roots from growing outside of the pots and both are quite effective. RootRight appears to be a little less toxic to the plants.

Establishing crapemyrtle into a tree form takes a bit of negotiating. Gary Keever has been dealing with the suckers at the base of crapemyrtles to ascertain which product or technique works best in minimizing sucker growth and promoting desired tree shapes. TreHold is a sprout inhibitor which was applied to the base of the cuts. Experiments were done with a product called ClipClean which is a device made of pruning shears with an attached container. The device was manufactured to douse the shears with an alcohol solution to disinfect after each cut so that the user wouldn't contaminate other plants. For ease in application Gary filled the container with TreHold so you cold cut suckers and suppress further growth in one procedure. This process worked well but the company now manufactures TreHold as an emulsion wax which is safer but no longer works in the ClipClean apparatus. Applications of the new emulsion to crapemyrtle have discolored the trunk and caused some peeling.

Future work will be done to determine why this happened. In addition to the crapemyrtle work Gary will be growing four azalea cultivars in the Camp Hill Experiment Station in an effort to develop plants that are healthier which will render them good crops for nursery growers.

His third demonstation addressed manipulating the length of light on perennial crops. Artificial light from 10 p.m. to 2 a.m. resulted in plants that flowered up to 40 days sooner and with many more flowers. This kind of information could help extend the marketing time for perennials. Cold hardiness of plants grown with extra light is being examined.

Controlling spurge and bittercress is a bothersome problem. Charles Gilliam is looking at 10 different products. Rout and Corale gave the best control along with Rigor-0-0. The goal of this research is to find a product that would work with one annual application. During this investigation Charles found that some herbicides can be used for turf and plants. Manage worked very well to control nutsedge; however, it is quite expensive.

Using new products in new ways to control foliar diseases was presented by Austin Hagan. He has found that Compass (daconil ultrex) does the job best. Drenches don't work that well. For powdery mildew on dogwood most products were fairly effective. Miracid worked best on roses for the treatment of blackspot but they must be sprayed weekly. Heritage and Eagle did well on the foliar diseases that plague crapemyrtles.

James Altland, a doctoral student, presented his study on postemergence bittercress control. Manage and Image worked best. The challenge of his research is to determine how much of particular products can be used to effectively kill the weed without negatively impacting on plant size. Galley worked well on azaleas at the recommended package rate.

Another doctoral student, Janna Glenn, presented her research on the use of paper pellets in container plantings. Placing a layer of paper pellets (from one to two centimeters deep) in the bottom of the pots helps reduce nitrogen leachate as well as produce plants that are greener and 20% larger.

Chazz Hesselein is performing a fern fertilization trial to compare the quality of plants relative to the rates of fertilization.

He has also been looking at the control of T-scale on holly, a pest that is difficult to control and can render plants unsaleable. Since T-scale grows on the underside of leaves it is difficult to apply a spray. A systemic material is needed that would let the plant get the insecticide to the insect. Orthene and Pinpoint have been effective. Asphate products worked well. Regarding Florida wax scale, Chazz has found that Sunspray, an oil, works best. If you leave it untreated the leaves will blacken with sooty mold.

(From David Morgan's newsletter: Weekly NMPRO).

Pecan trees (in the southwest) require the annual application of zinc to prosper. Crumb rubber gives off zinc. The main question addressed was whether placing crumb rubber in vertical holes within the drip line of 6 year old pecan trees would influence the mineral content of the leaves. The crumb rubber, in two different sizes, was placed in mesh tubes so it could be removed and tested for degradation at the end of the study period.

Zinc is the primary micronutrient of pecan trees. Zinc deficiency can be a problem. To prevent small leaves and a small harvest, zinc is applied annually at bud break and then every two to three weeks until terminal growth ceases. These annual zinc applications maximize pecan yields. Results of the study indicated that the crumb rubber applied as a vertical mulch increased the foliar zinc levels in all treatments.

More research needs to be done on plants that are less zinc tolerant.

(from a paper by Frank Matta, David Tatum and Francisco Salcedo of Mississippi State University).

SpinOut is a commercial product that the manufacturer claims increases root branching which increases fertilizer uptake, water absorption and overall increased plant growth. The active ingredient is copper hydroxide which burns back the root tip. SpinOut is applied to a cloth which is placed inside the socket pot or else painted onto the inside of the socket pot.

Crumb rubber possesses some of the same properties as SpinOut. Zinc is slowly released from the crumb rubber. A study was conducted on bradford pear and magnolia grandiflora and a rating scale was developed that went from 1, no roots outside the container, to 8, where the plant was impossible to harvest.

Results indicated that SpinOut worked better than the crumb rubber. Supposedly, tires have a zinc content of 2% but that appears to be highly variable. Also, there may be a difference in the zinc oxide content between the thread or sidewall of the tire. The study showed that 2% zinc doesn't control rooting-out in the pot-in-pot production systems.

More studies will be conducted to observe root circling of plants in container production.

(from a study by David Tatum, Frank Matta and Kerry Johnson at Mississippi State University).

Most of September was dry with the exception of 2-3 good rain events. Our September plant disease samples included the following: southern blight (Sclerotium rolfsii) on Japanese anemone; Colletotrichum leaf spot on Anthurium; Cercospora leaf spot on azalea; Pythium root rot on azalea; Cercospora blight on Leyland cypress; Cercospora leaf spot on dogwood; anthracnose on euonymus; scab (Elsinoe) on euonymus; Cercospora leaf spot and Phytophthora & Pythium root rot on hydrangea; Phytophthora & Pythium root rot on English ivy; Pythium root rot on Loripetalum; Phytophthora & Pythium root rot on pansy; Fabraea (Entomosporium) leaf spot on Bradford pear; southern blight on celadine poppy; southern blight on primrose sundrops.

Cercospora blight on Leyland cypress causes a blight of twigs. Usually disease begins on lower, inner twigs/foliage where conditions are more humid. Disease was confirmed by microscopic evidence of Cercospora spores. Control involves protective sprays of Cleary's 3336. Sanitation may not be practical, but clean-up of fallen foliage would help.

Anthracnose occurred on anthurium and euonymus. Brown leaf spots may be small-large, circular-irregular in shape. Some lesions may occur along leaf veins or at leaf edges. Tiny, pin-point spore masses were present and observed on some leaf spots. Spore masses are seen more readily with a hand lens or stereo microscope. Anthracnose disease control typically requires sanitation of fallen leaves. With herbaceous plants or small trees, protective fungicide sprays may be recommended.

A number of the disease reports of September were root/crown rot problems. Phytophthora root rot was diagnosed in both woody and herbaceous samples of hydrangea, English ivy, and pansy. Root decay caused by this fungus can cause death of the affected plant. Infected areas of lower stems (crowns) and roots decay as a soft rot in the presence of wet soil conditions. Phytophthora is a 'water mold' and, as such, it develops and causes disease spread and development only in wet locations. As infections age and plants begin to die, the rotted areas dry out. Disease may develop after plant roots have been stressed or injured by drought or excessive application of fertilizer. Then, when wet conditions occur, the environment is conducive for Phytophthora development and weakened plants are more susceptible to disease. The droughty conditions earlier in July-early September may have stressed plants so that they were more susceptible to root disease when wet conditions finally occurred. Poorly draining soils are also conducive for Phytophthora root disease. Control in a nursery involves sanitation and water control and sometimes protective fungicide drenches.

In homeowner situations, where situations involve a small number of plants, protective fungicide drenches are usually not a practical and economic recommendation. Crop rotation is sometimes helpful in the landscape situation. Pythium is another 'water mold' that usually causes root disease of herbaceous plants and foliage blights of certain turf grasses. Pythium may cause root disease of woody seedlings or severely stressed woody plants. In September, Pythium root decay was identified on Loripetalum, begonia, hyrdrangea, English ivy, and pansy. Disease symptoms are similar to the water-soaked description for Phytophthora. Usually culture or ELISA work is needed to distinguish between Pythium and Phytophthora. Control recommendations for Pythium root decay are similar to Phytophthora disease control. See the AL Pest Management Handbook for specific fungicide recommendations.

Fabraea (Entomosporium) leaf spot on Bradford pear was fairly common in September. Spots are generally black, small and rounded. A hand lens or a stereo-microscope will reveal the presence of small black pin-sized swellings. When mature, these swellings will crack open and microscopic spores of the fungus are evident upon examination with a compound microscope. Control requires clean-up of fallen leaves. For protective fungicide sprays, see the Alabama Pest Management Handbook.

John Olive at the Spring Hill Ornamental Horticulture Substation in Mobile reported seeing Rhizopus stem rot of poinsettia. The disease is typically observed as a black, glassy rot of stems. Dieback will result from the cankers and stem rot areas. On Leyland cypress, a Cercospora blight was noted. Lower and inner foliage is typically affected first. Also, Phytophthora root rot & stem rot were noted on English ivy. Roots develop a brown, wet decay and lower stems also develop a wet brown-black decay. In some situations, the decay appears as an internal vascular discoloration with resulting dieback of vines. Removal of infected plants is recommended. Soil drainage should be improved. Irrigation should be reduced, if appropriate. Protective fungicide drenches are labelled; their use is most practical in nursery situations. See the Alabama Pest Management Handbook for a list of recommended fungicides.

Disease problems usually decline in October as temperatures drop and the summer field and garden crop season is largely over and the fall-winter plantings of small grains, have not yet begun or are just beginning. But, we still commonly see forage problems, landscape ornamental problems, greenhouse/nursery crop problems, vegetables from fall gardens, and field plantings of vegetables in the southern-most sections of the state.

At this time of the year we often see pansy diseases. Watch for leaf spots, crown rots and root rots.

The list below includes some common disease problems received in the lab during October of the past few years. Comments on control practices are brief. Refer to the Alabama Pest Management Handbook or individual spray guides or fact sheets for details.