Callicarpa Americana Research Articles

Control of Oaks (Quercusspp.) and Associated Woody Species on Rangeland with Tebuthiuron

Aerial applications of 20% tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N-dimethylurea} pellets at 2.2 kg/ha (ai) in the spring effectively controlled post oak (Quercus stellataWangenh.), blackjack oak (Q. marilandicaMuenchh.), water oak (Q. nigraL.), yaupon (Ilex vomitoriaAit.), winged elm (Ulmus alataMichx.), downy hawthorn (Crataegus mollisScheele), gum bumelia [Bumelia lanuginosa(Michx.) Pers.], and willow baccharis (Baccharis salicinaTorr. & Gray) in the Post Oak Savannah of Texas. Tree huckleberry (Vaccinium arboreumMarsh.), black hickory (Carya texanaBuckl.), honeylocust (Gleditsia triachanthosL.) and cedar elm (Ulmus crassifoliaNutt.) were partially controlled by 2.2 kg/ha of tebuthiuron. Canopies of buckbrush (Symphoricarpos orbiculatusMoench), southern dewberry (Rubus trivialisMichx.), American beautyberry (Callicarpa americanaL.), and persimmon (Diospyros virginianaL.) were reduced for about two growing seasons after which the woody species recovered. American beautyberry appeared to increase in abundance by the third growing season after control of the other woody species. Honey mesquite [Prosopis juliflora(Swartz) DC. var.glandulosa(Torr.) Cockerell], eastern redcedar (Juniperus virginianaL.), and Texas persimmon (Diospyros texanaScheele) were not controlled by tebuthiuron at 2.2 or 4.4 kg/ha, and saw greenbrier (Similax bona-noxL.) and peppervine [Ampelopsis arborea(L.) Koehne] apparently increased following application of tebuthiuron.

Effect of Forest Clear-Cut Edge on Breeding Birds in East Texas

Effect of Forest Clear-Cut Edge on Breeding Birds in East Texas

Control of Live Oak (Quercus virginiana) and Understory Vegetation with Soil-Applied Herbicides

Soil-active herbicides were investigated for control of live oak (Quercus virginianaMill.) on the Texas Coastal Prairie and Claypan areas with and without mechanical treatment. Roller chopping before, during, or after herbicide application had very little influence on mortality of live oak compared to the herbicide applied alone. Roller chopping did allow increased grazing of livestock for at least 3 yr after knockdown of the brush. Tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} was generally the most effective herbicide for live oak control; bromacil (5-bromo-3-sec-butyl-6-methyluracil), karbutilate [tert-butylcarbamic acid ester with 3(m-hydroxyphenyl)-1,1-dimethylurea], and picloram (4-amino-3,5,6-trichloropicolinic acid) were somewhat less effective, especailly at 2.2 kg/ha. Limited data suggested that hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl]-1,3,5-triazine-2,4(1H,3H)-dione] also was highly effective for control of live oak. Primary invaders on either mechanically or chemically treated areas were American beautyberry (Callicarpa americanaL.), southern dewberry (Rubus trivialisMichx.), boneset (Eupatorium perfoliatumL.), yankeeweed (Eupatorium compositifoliumWalt.), brownseed paspalum (Paspalum plicatulumMichx.), and carpetgrass (Axonopus affinisChase). A herbicide was generally equally effective for live oak control whether applied broadcast or in rows as granules, or applied as sprays to the soil surface or subsurface.