Technical Note: Afforestation in North Mississippi on Retired Farmland Using Pinus echinata: First-Year Results

In March 2005, 1-0 bareroot shortleaf pine was planted on retired fields of the Mississippi Agriculture and Forestry Experiment Station near Holly Springs, Mississippi. Objectives of the study were to evaluate (1) subsoiling and (2) herbaceous weed control (HWC) on 1st-year seedling survival and size. Treatments were replicated three times in a randomized complete block design. The subsoiling treatment was completed in December 2004. The HWC treatment was 4-oz Arsenal AC + 2-oz Oust XP product per sprayed acre applied in a 4-ft band over the row in April 2005. In addition, mowing was completed three times between rows during the first growing season. First-year seedling measurements were completed by March 2006 on seedling survival, groundline diameter (GLD), and total height. Subsoil tillage did not have a significant effect on 1st-year survival, diameter, or height. HWC had a significant effect on shortleaf GLD but not survival or height.

Survival of Planted Oak Seedlings is Improved by Herbaceous Weed Control

Sulfometuron was applied at 0.1, 0.15, and 0.2 kg ai/ha over the top of oak seedlings. Three separate field studies were completed. In 1997, 0.1 and 0.2 kg ai/ha was applied PRE over six oak species. In 1998 and 1999, 0.1 and 0.15 kg ai/ha were applied PRE and 0.1 kg ai/ha was applied POST over two species of oaks. Results demonstrate that first-year survival of oak seedlings is greater in areas which receive competition control. Survival was 21 to 44% greater in treated areas as compared to nontreated areas. Observations indicate that survival differences are increased in droughty years. Competition control appears essential to obtaining desirable levels of survival when oak seedlings are planted in areas with established herbaceous competition.

Identifying Intensively Managed Pine Plantation Acreage in the South

Long-term timber supply projections are a function of many factors including the intensively managed southern pine plantation area. A survey of southern forestry herbicide distributors was developed to determine the acreage of southern pine plantations that included herbicide applications in the management regime. Survey techniques are discussed and herbicide-treated pine plantation acres are reported by subregion, type of sale (turnkey or direct), and type of treatment (site preparation, pine release, or herbaceous weed control) for 2001 and 2002. The survey methodology produced technically acceptable results; however, the marketing and competitive aspects of the data proved to limit survey participation. A usable survey method is described with a potential for future timber supply modeling application. South. J. Appl. For. 29(3):163–166.

Assessing the Use of Chopper Herbicide for Establishing Hardwood Plantations on a Cutover Site

Successful establishment of hardwood plantations requires effective weed management. Mechanical weed control is inefficient, and few herbicides are available for use in hardwood plantations. In an effort to identify new chemical control options, the potential of imazapyr (Chopper herbicide) for site preparation prior to planting three common southern hardwood species was assessed. Twelve site preparation treatments were tested using Chopper applied at four rates and three timings prior to planting. Each site preparation rate and time pairing was repeated under two postplant herbicide regimes—directed glyphosate (Accord herbicide) sprays designed to maintain weed-free conditions and a single broadcast sulfometuron methyl (Oust herbicide) treatment designed to test a potential operational sequencing of Chopper site preparation followed by herbaceous weed control. Although results must be evaluated in the context of a single site and set of environmental conditions, they demonstrate the utility of Chopper herbicide for site preparation prior to planting hardwoods. For sycamore (Platanus occidentalis L.)and sweetgum (Liquidambar styraciflua L.),site preparation before the end of July with Chopper rates up to 64 oz/ac improved survival and growth over postplant treatments alone. For later season applications, sycamore and sweetgum were more sensitive to the Chopper site preparation rate. For Oct. site preparation, Chopper rates above 16 oz/ac adversely affected planted sycamore seedlings and rates greater than 32 oz/ac adversely effected planted sweetgum seedlings. Cherrybark oak (Quercus pagoda Raf.)performed best using the highest Chopper rate of 64 oz/ac regardless of timing. South. J. Appl. For. 28(3):163–170.

The Effect of Hexazinone, Sulfometuron, Metsulfuron, and Atrazine on the Germination Success of Selected Ceanothus and Rubus Species

This study documents the impact pre-emergent forestry herbicides have on germination of some selected seral woody competitors in the Pacific Northwest. Four commonly used pre-emergent soil-active herbicides (hexazinone, sulfometuron, metsulfuron, and atrazine) typically used for herbaceous weed control were applied at six rates over stratified seed of Ceanothus velutinus (CEVE) and Ceanothus integerrimus (CEIN) in a greenhouse efficacy trial. In addition, hexazinone and sulfometuron were applied over stratified Rubus ursinus (RUUR) and Rubus parviflorus (RUPA) seed and sulfometuron over stratified seed of Rubus spectabilis (RUSP) at the same six rates. Numbers of seed to successfully germinate and develop true leaves were counted over a 9 wk period immediately following herbicide application. The hexazinone treatments reduced germination and growth of CEVE, CEIN, and RUPA. The RUUR species was tolerant of the hexazinone herbicide at low rates but at higher rates was strongly affected. The sulfometuron treatments had less effect on survival probability than hexazinone but strongly reduced the average dry weight of plantlets of all species. Seedling dry weight decreased with increasing rate of both metsulfuron and atrazine. Increasing the metsulfuron rate reduced the probability for CEVE seedlings to survive but not CEIN. Finally, atrazine sharply reduced the plantlet survival and reduced dry weight of both CEVE and CEIN even at low rates.West. J. Appl. For. 17(4):194–201.

Six-Year Development of Regenerating Natural Hardwood Stands with HerbaceousWeed Control

A study was established to examine the effects of herbaceous weed control (HWC) on the development of natural hardwood stands in southeastern West Virginia. In two Appalachian mixed hardwood stands, HWC treatments, consisting of Oust (4 oz/ac) or Oust (4 oz/ac) + Escort (1 oz/ac), were applied prior to budbreak during the first or second growing season after clearcutting. Fern and Rubus species dominated the herbaceous plant cover in the first 3 yr following treatment. Oust + Escort plots had significantly less total herbaceous plant cover than the check plots in the first 2 yr. Mean plot-level treatment effects were significant only in one of the two stands. Sixth-year average tree heights on HWC plots at one site were greater than those on the check plots, and ranged from 11.4 ft (Oust + Escort) to 9.2 ft (check). Six-year heights of tagged stems were greater for Fraser magnolia (Magnolia fraseri Walt.) on HWC plots. Although black cherry (Prunus serotina Ehrh.) had the greatest extent of crown damage from the herbicide treatments initially, average heights of tagged black cherry stems in both stands ranked higher on the HWC plots than on the check plots.