Stan Reinke
Introduction
Ashe juniper is commonly controlled by grubbing or dozing on the Edwards Plateau at a cost of $40-50 per acre or more depending upon its density. Not only is this cost difficult to recover from added forage production, but it also leaves pastures in an extremely rough condition, often turns up large rock fragments , scatters pricklypear, and damages the grass turf. In the last 4 years, the NRCS has worked with landowners in two counties on the Plateau with different cedar management scenarios which have proven to be cost effective and highly efficacious in terms of cedar mortality.
In Eastern Schleicher County, near Ft. McKavett, on the Bolin Ranch which is leased and operated by Jimmy Powell, juniper was initially controlled by one-way chaining at a cost of $8.71 / acre. The pasture is 669 acres and consists of mostly shallow and low stony hill range sites with a limited amount of clay loam site. The pasture was chained in February 1993 and was grazed only once for a 2-week period during the growing season with a herd of sheep and cattle.
The pasture was prepared for burning in January 1994 by blading fireguards with a bulldozer around the perimeter of the pasture and by blading interior fireguards on the north and east sides of the pasture approximately 500 ft inside the perimeter fireguard. Total cost of the bladed lines for the entire pasture was $1.67/acre.
Blacklines were burned on February 4, 1994 with an 8-man crew including 2 livestock sprayers. Weather conditions for blacklines were 87% relative humidity, average temperature of 57 oF and easterly winds of 3-6 miles/hour. Numerous spot fires occurred outside the blackline area but were controlled by ground crews. Mainfires were lit approximately 2 weeks later. Mainfire weather conditions were 24% relative humidity, air temperature of 81o F and southwesterly winds of 3-9 miles/ hour.
Cedar mortality counts were made throughout the pasture with belt transects several months following the burn. Cedar mortality in the blackline was 38%. In the mainfire cedar mortality was 91%.
The grass lease is going for $4.00/acre. Considering that the pasture was rested almost one full year from February 1993 until February 1994 and again during March-May of 1994 to allow forage recovery, the total cost of grazing lost was approximately $5.00/acre (1.25 yr). The total cost of this brush control, including chaining, fireguards and deferment was $15.38/acre.
Another Example
The second scenario occurred in central Kimble County approximately 8 miles west of Junction on the Jo Ella Bolt Ranch operated by Ward Whitworth and David Murrow. Juniper was initially controlled by hand cutting at a cost of $42.00/acre. The pasture is 800 acres, extremely rough, dissected by numerous canyons and steep sloped draws and consists of mostly low stony hill and steep rocky range sites.
The pasture was rested January-December 1995 to build a fine fuel load and January to October 1996 for recovery purposes. According to Ward Whitworth, annual grass lease on this ranch is $2.00/acre. This pasture was rested a total of 23 months prior to and after the fire for a deferment cost on a cash lease basis of $3.84/acre.
The pasture was prepared for burning in January 1996 by blading fireguards with a bulldozer around the perimeter of the pasture and by blading interior fireguards on the north and east sides of the pasture approximately 500 ft inside the perimeter fireguard. Total cost of the bladed lines was $1.91/acre.
Blacklines were burned on 2 different days in mid March due to length of the blacklines and weather conditions. The eastern blackline was burned at night. Weather conditions for blackline burning ranged from 34 to 47% relative humidity, temperatures of 30 to 53oF and north-northwesterly winds of 4 to 10 miles/hour. Green cedar moisture during blackline and mainfire burning was 85%.
The mainfire was burned the first week in April. This was later than normal but green-up had not occurred due to dry spring weather. Mainfire weather conditions were 30 to 42% relative humidity, air temperatures of 78 to 82oF and south-southwesterly winds of 8 to 11 miles/hour.
Cedar mortality counts were made throughout the pasture several months following the burn. Cedar mortality in the blackline area was 31%, while that in the mainfire area was 93%.
The costs of this burn and the consequent brush control including hand cutting, fireguards, and deferment was $47.75/acre.
Whereas the chain/burn scenario will always be the least expensive of all control types applied to larger juniper, there will be some operators who choose to hand cut cedar. Hand cutting will be chosen because of aesthetics, inaccessibility of the terrain to crawler type tractors or the desire to conserve the more desirable browse plants. Based upon results in the counties described, either treatment presents viable options for landowners interested in cedar control.
Comments: Allan McGinty, Professor and Extension Wildlife Specialist