Virginia Creeper (Parthenocissus quinquefolia) and Wild Grape (Vitisspp.) Control in Fraser Fir

Virginia creeper and wild grape are troublesome perennial vines that often infest Christmas tree plantations. Field studies were conducted to evaluate Fraser fir injury and Virginia creeper and wild grape control with directed applications of triclopyr (1,680 g ai/ha) alone and in combination with 2,4-D (1,120 g ai/ha), clopyralid (280 g ai/ha), and halosulfuron (36 g ai/ha). Additional treatments included 2,4-D, clopyralid, glyphosate (1,120 g ai/ha), halosulfuron, hexazinone (560 g ai/ha), mesotrione (105 g ai/ha), and sulfometuron (71 g ai/ha) applied alone; and a mixture of hexazinone plus mesotrione. In the triclopyr-containing treatments, Fraser fir injury ranged from 6 to 13% at 1 mo after treatment (MAT) and was 4 to 8% at 11 MAT. Leader growth was not impacted by the herbicide treatments. At 11 MAT, all triclopyr-containing treatments controlled Virginia creeper 93 to 98% and wild grape 98 to 100%, which was greater than the control observed with glyphosate at 63 and 59%, respectively. Virginia creeper and wild grape control with 2,4-D was 88 to 90%. Clopyralid, halosulfuron, hexazinone, hexazinone plus mesotrione, mesotrione, and sulfometuron provided less than 66% control of both perennial vines. Directed applications of triclopyr-containing treatments or 2,4-D were effective management tools for selective removal of wild grape and Virginia creeper from Fraser fir Christmas tree plantations. Additional research is needed on the potential sensitivity of other commonly grown Christmas tree species to triclopyr-containing treatments.

CONSUMER PREFERENCE FOR ALTERNATE CHRISTMAS TREE SPECIES

A survey was developed evaluating the preference of consumers for purchasing three alternative Christmas tree species. Trees included: Pinus virginiana, a traditional Alabama Christmas tree; a containerized Ilex × `Nellie R. Stevens'; and a cut × Cupressocyparis leylandii. Virginia pine and leyland cypress were rated higher than the holly. The average rating on a scale of 1 to 5 for the Virginia pine and the leyland cypress was 3.75 and 3.63, respectively. Consumers rated the holly an average of 3.29. A rating of 1 indicated a strong negative response and a rating of 5 offered a strong positive response for buying the tree. The median rating for all three species was 4, indicating that 50% of the participants rated them a 4 or higher. The mode, or most frequent rating, was 5 for all three species. Although the average rating for the holly was lower than the average for the Virginia pine and leyland cypress, the holly and the leyland cypress may have a market niche with >50% of the respondents indicating that they would purchase the trees.

Propagation of Fraser Fir

Fraser fir [Abies fraseri (Pursh) Poir.], the most important Christmas tree species in North Carolina, is rapidly gaining popularity nationwide. It is propagated by seed, but special needs such as genetic improvement will involve use of grafting, air layering, propagation by stem cuttings, and micropropagation (tissue culture). This paper summarizes research conducted to date on Fraser fir concerning these techniques in addition to information regarding seed production and sexual propagation.

Effect of Water Additives on Fraser Fir Needle Retention

Several floral and tree preservatives were evaluated to determine their effect on postharvest needle retention of Fraser fir [Abies fraseri (Pursh) Poir.], an important Christmas tree species. Clorox (sodium hypochlorite) and aspirin (salicylic acid) caused massive needle loss, and three of the six commercial additives increased needle loss significantly, No treatment was better than water alone.

Effects of Frequency of Chemical Weed Control on Growth and Quality of Christmas Trees1

Effective weed control is essential to the production of high-quality Christmas trees on most planting sites. Many growers use herbicides applied along rows of trees, in combination with mowing between rows, to control competing grasses and broadleaved weeds. This study evaluated one-time, biannual, and annual applications of herbicide during a 6-year period on growth and quality of different Christmas tree species planted on moderately dry and moist planting sites. Increased height growth from more frequent applications was limited primarily to the drier site, and even on that site rotation length would have been reduced by only 1 year. Christmas tree quality, as reflected by foliage density and tree weights, generally improved on both areas as herbicides were applied more frequently. Colorado spruce, Douglas-fir, and Fraser fir benefited more than Scotch and white pines. North. J. Appl. For. 6:15-17, March 1989.