Patch or spot scarification prepares a cutover or herbaceous covered site to create open microsites. Plant bareroot and container stock, or sow tree seeds through various means of application on the prepared sites.
Sites conducive to surface scarification are described as follows
Patch scarification can be done any time during the frost-free season. The preferred period is from about August 1st until the trees are planted or seed applied. Patch scarification, however, can be used before August 1st on light soils with small amounts of competition. Sites dominated by upland brush species (hazel, raspberry, etc.) can effectively be scarified but will usually need additional site prep or release with herbicide.
A prime mover is required to pull the Leno or Bracke. They were designed to be pulled by the common 4-wheel drive full length tree skidder equipped with a rear butt plate upon which the hitch is mounted.
The skidder must have an overhead cable or hydraulic winching device to raise and lower the Leno. The winch must have the ability to lower the 3,500 pound Leno at a slow speed so the axles are not damaged.
There are two ways the Leno can be seriously damaged—by dropping and backing up. The former can bend the axle and the latter can damage the timing mechanism (accumulator). Potential problems should be noted in the skidder contract and the operator held responsible.
On level terrain with light soil, a 70+ HP skidder will suffice. On heavier sites with steep or broken terrain, a skidder with 90+ HP is recommended. Oversized tires are very beneficial. They offer additional traction and allow access through wet sites, which might stop regular size equipment.
The Leno ripping wheels are spaced on a 6 foot center with an 18 inches cutting width which cannot be adjusted. All spacing control is maintained by a combination of skidder travel speed, travel location to adjoining scarified strips, and proper setting of the timing mechanism in the cutting wheels. Depending upon surface conditions, a certain degree of continuous disturbance occurs between the scalps. About 40 percent of the site is scarified. A second treatment at right angles to the first pass will scarify about 70 percent of the area. This is a desirable procedure prior to direct seeding.
The operational techniques of the Bracke scarifier are very similar to the Leno. The Bracke offers some advantages in that its use is more suitable for "difficult" sites, and adjustments can be made very easily to the scalping spacing.
The seedling should be placed on the shoulder of the scalp near the intersection of the organic berm.
Site Prep, Patch Bracke Leno, Forest Development Manual, 1994, ed., 10/2008