Archive | August, 2016

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/.