Sunburn on crapemyrtle?

4 Aug

Crime scene: a parking lot in DFW area (more details in the Sept/Oct issue of 2016 TNLA GREEN magzine).

There were three rows of crapemyrtle trees in the parking lot. The picture of each row was taken from the south end. The trees in the left row had overall the best health, the middle row the worse and the right row in between. Within a row, plants on the south end (close to the shopping areas) seemed to be in worse condition than the north end, and the west side worse than the east side. On most trees, the damage on bark seemed to be worse on the upper trunk (about 5’ above ground, where trees branched out) than the lower trunk.

What’s different among these rows of crapemyrtles? The left row only has marked parking space on the east side of trees . The parking spaces are at a right angle to the right row on both sides. Here comes the problem. My eye level is about where trees branching out. It was about 2:30 pm. When I stood next to a tree in the middle row facing west, the glaring sunlight reflected right into my eyes . I felt I hit the jackpot here! I stood next to other trees. The reflected glaring sunlight followed me, everywhere there was a vehicle. Two O’clock in the afternoon is normally the hottest time during a day. Sunlight is much stronger around 2:30 pm than 6:00 pm, when sunlight is reflected to the canopy on the right row.

So why are trees on the south end worse than north end? Probably because a popular grocery store is on the south side of the parking lot and customers park as close as they can to the store (i.e. south end of each row). I hope we solved the homicide here. But I’d love to hear from you if you have a different opinion. Email me at mgu@tamu.edu.

Vein pocket gall on red oak

4 Aug

A colleagues shared pictures of this cool-looking (not so cool to the owner of the red oak) ‘cancer’, vein pocket gall. At this stage, not much can be done. Find more at Dr. Mike Merchant‘s bloghttp://citybugs.tamu.edu/2010/06/28/the-gall/.

Crapemyrtle bark scale update 06/01/2015

2 Jun

For all the crapemyrtle bark scales fan: we’re using double-sided sticky tape to monitor scale crawlers at various locations (three shared here). With the peak in May in two Texas locations, I feel Little Rock will see a summer peak pretty soon. Comments?

Picture1  Picture2Picture3

Flowers are for girls! So gardening is for boys!

24 Apr

Check out this Walmart commercial.

Walmart flower

Crop safety: Pyrifluquinazon, Spirotetramat &Tolfenpyrad

21 Apr

From IR-4:

Pyrifluquinazon Crop Safety Summary

Pyrifluquinazon was registered for use on greenhouse ornamental horticulture crops as foliar sprays in the United States in 2013 to manage whiteflies, aphids, leafhoppers, chilli thrips, and mealybugs. The label contains a list of crops tested for tolerance. From 2010 to 2014, the IR-4 Project conducted 92 trials on 24 ornamental plant species examining phytotoxicity related to pyrifluquinazon applications. No tested crops exhibited significant injury or growth reduction during these experiments. It is recommended that Bacopa sp. be added to the list of tolerant crops.

Spirotetramat Crop Safety Summary

 

Spirotetramat was registered as Kontos for use on ornamentals applied foliar or drench in the United States in 2008. The label recommends use on ornamental horticulture plants except a few species or genera specified in the label. From 2007 to 2013, the IR-4 Project conducted 225 trials on 49 ornamental plant species examining phytotoxicity related to Kontos applications. In these trials, only 6 crops (Begonia sp, Coleus x hybridus, Petunia sp., Pelargonium sp., Vinca sp.,and Viola sp.) exhibited noticeable, significant injury and that was a slight height reduction, leaf curling, bleaching of flowers or plant death at the 2X and 4X rates applied as drench. One species (Verbena hybrida) exhibited significant flower discoloration at all rates applied as drench in one trial. Based on this information, it is recommended that the label prohibits drench application on Begonia sp., Coleus x hybridus, Petunia sp., Pelargonium sp., Verbena hybrida, Vinca sp.,and Viola sp.The current label does not recommend use of Kontos on Pelargonium spp. Foliar application on these species may be recommended with the precautionary statements in the CROP TOLERANCE section of the current Kontos label.

 

Tolfenpyrad Crop Safety Summary  

Tolfenpyrad was first registered as Hachi-Hachi 15 EC in the United States on July 28, 2010 for the control of aphids, leafhoppers, scales, thrips, whiteflies, and early instar lepidopteran larvae on ornamental horticulture crops grown in greenhouses. An expansion of this label for outdoor uses is planned. The IR-4 Project completed 160 trials on 24 ornamental plant species from 2010 through 2014 examining phytotoxicity related to foliar applications of Hachi-Hachi 15EC or Hachi-Hachi SC. In this report, 11 species or genera exhibited minimal or no injury after foliar treatments of Hachi-Hachi 15EC (tolfenpyrad) at 21, 48 and 84 fl oz per 100 gal. All can be added to the label as crops tested for tolerance: (Alyssum sp., Angelonia sp., Antirhinnum sp., Begonia sp., Chrysanthemum/Dendranthemum sp., Dahlia sp., Petunia sp,. Tagetes sp., Verbena sp., Viola sp. and Zinnia sp.). For Hachi-Hachi SC, 12 crops can be listed on the label as crops tested for tolerance (Alyssum sp., Angelonia sp., Antirhinnum sp., Bacopa sp., Begonia sp., Dahlia sp., Gerbera sp., Petunia sp., Tagetes sp., Verbena sp., Viola sp. and Zinnia sp.), and two crops should be included in listing of crops where treatments are not recommended: Impatiens sp. and Impatiens, New Guinea Hybrids.

“Aster Yellows”—–very unusual, but not necessarily good

8 Sep

Alien Plant Take Over Your Flowers? No—It’s “Aster Yellow”

See the original post here.

Posies in a panic: tufted leaves that erupt amid a flower head tells you a deadly killer is at work. Read on ....

Gardening can prolong life in over 60s

2 Nov

People aged over 60 years can cut their risk of heart attack and stroke and reduce their risk of death by as much as 30% by being generally active and indulging in regular home improvement activity or gardening, research published online in theBritish Journal of Sports Medicine has shown.—–from http://www.bmj.com/content/347/bmj.f6506.

Follow

Get every new post delivered to your Inbox.

Join 246 other followers