Short Hort Notes

 

September 12, 2006
 
*Recent Problems:
Ash trees - possible ash yellows or eriophyid mites causing witches' broom formations - also lack of water/drought causing leaf marginal necrosis on other ash trees.
Primrose indoors - marginal necrosis - possible causes might include natural senescence of lower leaves, salt buildup in the growing medium, high light.
Drip irrigation problems on mature shrubs and trees - root systems have grown beyond the reach of the drip system and plants are showing drough symptoms as a result.
Spruces dying from the top down - possible western spruce budworm.
Brown turf - most likely caused by mowing too short - recommended height is 2-1/2 to 3 inches.
Mushrooms in lawns - as soon as the sun comes out and things dry out, they are generally gone.
Water quality issues for greenhouse/nursery crop production - well water versus city water - depends on water analysis.
Solid garlic bulbs - sometimes these 'rounds' are caused by inadequate cold temperatures during overwintering. Usually they will form segments or cloves following proper chilling during winter months.
Pear slugs on cotoneaster - it's getting a little late in the growing season to try to control  these as freezing temperatures will put a stop to them. If they persist next season, a contact insecticide could be used.
Vagabond galls on cottonwoods - don't really harm the trees but can be pruned out if needed.
Powdery mildew on zucchini - another pest (fungus) that does not really harm the plants - it's late in the season and controls are not warranted.
 
*Help for Choosing Trees: The Northern Trees site (http://orb.at.ufl.edu/TREES/index.html) helps consumers select trees in USDA Hardiness Zones 2-7. The site is a cooperative effort between Univ. of Fla., Rutgers Univ. and USDA Forest Service. The site was designed to provide extensive cultural and maintenance information. It allows user to develop lists of suitable trees based on soils, sites and plant attributes. The information is accompanied by photos. There's also a link for trees suitable for Zones 8-11.
 
*Abstract from Poster Presented at the American Society for Horticultural Science conference: 'Creating Videos to Enhance Student and Public Educational Opportunities in Landscape Management' by Sloane M. Scheiber, Jennifer Hitchcock, Sudeep Vyapari, and Lance Osborne, University of Florida.
    "A series of video clips and narrated PowerPoints were developed to aid in the presentation of common horticultural techniques. To determine the most effective format for delivery of horticultural subject matter, video clips and PowerPoints were developed for three topic areas and presented to two target audience groups. Target audiences consisted of Master Gardeners (Orange and Osceola County, Fla.) and future horticulture professionals (UF Environmental Horticulture students enrolled in Landscape Plant Establishment). Upon completion of viewing both media formats, participants were asked to complete a survey. Eighty-six percent of participants completed and returned surveys. Data were sorted and analyzed for calculation of mean percent for each response sought. Results of the survey indicated that, depending upon the topic, a higher proportion (66% to 93%) of Master Gardeners preferred narrated PowerPoints in comparison to video clips. However, 60% to 70% of students preferred video clips to narrated PowerPoints. In reference to the informative nature of both videos and PowerPoints, >67% of all respondents rated both media formats between good and excellent; however, most respondents indicated new information gained was less than 40%. Factoring the costs associated with production (about $1000 per video vs. essentially no cost for narrated PowerPoints) and participant responses, narrated PowerPoints appear the best option for conveyng common horticultural practices."
 
*In the Panter Back Yard: It froze last week - not hard enough to kill anything, but enough to knock down some of the warm-season annuals (impatiens, zinnias, etc.). There are still quite a few things blooming including the Japanese anemone, garden phlox, sedum, liatris, and many sages. The containerized annuals near the house were not affected by the cold temperatures and are still thriving. The possible exception is the calibrachoa in a hanging basket - cold air surrounds it at night and it is pretty close to done for the season! Calibrachoa is closely related to petunias (Solanaceae family) and prefers warmer temperatures. Tomatoes and raspberries are ripening nicely and carrots are ready to be harvested any time.
   
*Upcoming Events:
--International Society of Arboriculture - Rocky Mountain Chapter, Annual Conference 'The Business of Trees,' September 28-30, 2006, Hilton Fort Collins, Fort Collins, Colorado. Contact: kathleen@hughesstuart.com.
--Association of Specialty Cut Flower Growers National conference and Trade Show, October 26-29, 2006, San Jose, California. Contact: www.ascfg.org.
--American Society for Plasticulture conference, November 2-5, 2006, San Antonio, Texas. Contact: www.plasticulture.org.
--Tree Care Industry Expo, November 9-11, 2006, Baltimore Convention Center, Baltimore, Maryland. Contact: Tree Care Industry Association at 1-800-733-2622.
--Wyoming Groundskeepers and Growers Association Annual Conference, January 17-19, 2007, Parkway Plaza Hotel, Casper, Wyoming. Contact: www.wgga.org.
--ProGreen Expo, January 22-26, 2007, Colorado Convention Center, Denver, Colorado. Contact: www.progreenexpo.com or info@progreenexpo.com.
 
 
 
Karen L. Panter, Ph.D., C.P.H.
Extension Horticulture Specialist
Plant Sciences - Department 3354
1000 East University Avenue
Laramie, WY 82071
307-766-5117 office
307-766-5549 fax