Dnr silviculture handbook

Therefore, birch seed tree harvests are a common practice to attempt to promote natural birch regeneration. The desired future condition of these harvests is to maintain an aspen covertype while increasing or maintaining the paper birch component of the stand.

The mixed composition of aspen and birch is why the birch seed tree method was selected for stand tw A56 in the case study. The stand selected for the birch shelterwood method, tw Bi59, was a purer birch stand offering an opportunity to intensively manage for paper birch. The Wisconsin DNR recommends shelterwood harvests as a generally accepted practice for paper birch regeneration.

The Wisconsin DNR Silviculture handbook states that a shelterwood harvest provides enough shade to prevent desiccation and protect against competing plant growth.

For this case study, regeneration data was collected from both a seed tree and a shelterwood harvested stand in the Fond du Lac state forest. The close proximity and same habitat classification of the stands provided an opportunity to compare treatments on similar sites.

The objective of this harvest was to maintain paper birch as a component of these stands and document the extent of paper birch regeneration. This site was used to compare effectiveness of Paper Birch regeneration in a shelterwood harvest vs a seed tree harvesting method. It is a management objective of the Northern Superior Uplands Forest Plan to maintain or increase the paper birch covertype where possible. Revenue generation, capture volume of existing old stand and regenerate new vigorous stand of similar productivity and diversity with an increase in hardwood quality.

The prescription for the shelterwood site followed the Wisconsin DNR guidelines for a paper birch shelterwood harvest. Paper birch trees selected for reserve were healthy, large crowned, good form, high quality trees expected to promote the best genetic diversity of seed for the next stand.

Other species such as red oak and basswood were reserved to promote diversity within the site. Paper birch and basswood selected to be cut in the initial shelterwood harvest were painted. All aspen present on the site were reserved to reduce competition of root sucker aspen regeneration. Full tree skidding was required on the sale to facilitate scarification during logging operations.

The timing of the overstory removal harvest is dependent on regeneration, the Wisconsin DNR guidelines state that the removal harvest should occur in growing seasons after the initial harvest. The seed tree harvest was done under similar summer conditions, and also required full tree skidding to facilitate scarification.

On this site marked paper birch trees were harvested, leaving unmarked healthy, large crowned paper birch of good form as seed trees. All aspen, maple, basswood and balsam fir were harvested. Table 1: Harvest and reserve totals by treatment and also pre-harvest totals. For the shelterwood, harvesting began on August 2 nd , and ended on August 21 st. The treatment went as planned and created a moderate amount of scarification due to full tree skidding being required.

Almost all marked trees were removed from the site with the exception of some trees that the loggers were unable to harvest due to slope limitations. Soil conditions were satisfactory for a summer harvest, and no rutting occurred. Additional Scarification with a fire dozer and salmon blade was planned for this site that fall, post-harvest, but there was a long rainy period after the harvest that made it impractical to attempt to perform any scarification due to concern of rutting and compaction damage due to saturated soils.

The seed tree harvest went similarly well, without many difficulties. Harvesting occurred mainly in August and September of Full tree skidding, and seed tree distribution was satisfactory. No rutting occurred, and site conditions post-harvest appeared satisfactory.

Mechanical scarification was not planned for this site, but upon conducting the regeneration survey, we determined that full tree skidding may not have provided sufficient scarification for establishment of a seed bed for birch regeneration. Areas of dense aspen regen were avoided in the birch seed tree so that locations where birch had a chance to regenerate could be evaluated. All plots had a 6. A removal harvest on the shelterwood site is expected to be planned in winter or winter The harvest will most likely be an informal sale due to total residual volume being under cords and the desire to time the harvest with frozen ground soil conditions and sufficient snow pack to protect paper birch regenerants and seedlings on site.

Additional scarification may happen before the removal harvest, but is budget and weather dependent. If possible this scarification will be done with a salmon blade, which is a device that can be connected to the front end of smaller crawler dozer.

Additional revenue will be added from the overstory removal informal sale. Seed Tree Timber Sale Revenue: Paper Birch and Sugar Maple are the two most abundant species on these sites.

According to climate change response data provided by the Minnesota DNR, both species are predicted to remain stable in a wetter climate on this plant community. Paper birch is predicted to slightly decrease in abundance, while sugar maple is expected to increase in abundance in a warmer climate on this plant community. Leaving some sugar maple on this site allows for increased resiliency and long term adaptability for a future where climate change may have a drastic effect on the native tree species.

Also sugar maple due to its shade tolerance can form an additional cohort, intermediate and under the birch canopy, which maximizes site productivity and volume yield potential as it can grow in a different ecological niche that the shade intolerant paper birch.

The maple subcanopy increases forest structural diversity and heterogeneity, which is important for many birds species and other ecological values. There is a noticeable difference between the studied shelterwood and seed tree harvest. Birch regeneration in the shelterwood harvest is roughly 10 times the amount found in the seed-tree, especially in the regenerant category.

Many of the regenerants were found underneath competing vegetation, most notably red raspberry and bindweed. On the shelterwood site the competition of bindweed was sampled as a medium low presence with an average height of 1. Raspberry was measured to have a medium low presence with an average height of 2. But when you put the two together as they were sampled on the site you have a medium to medium-high amount of competition for those paper birch seedlings with an average height of 1.

On the seed-tree site the competition averaged a medium-low presence for bracken fern with an average height of 2.

Together competition was at medium level for bracken fern and beaked hazel with paper birch at an average height of 2. Going forward an emphasis will be made on revising each chapter on an individual basis. This will make the revision process more efficient thus providing the best customer service possible. Check this site periodically to view or download the most recent revisions. Revision dates can be found on the bottom of the page in each chapter.

Purpose [PDF]. Chapter 9 — Economics [PDF]. Appendices [PDF]. Wisconsin Forest Management Guidelines. Forest Management.