Now is a great time to start planning for tree planting next spring and site preparation is a critical component of that planning. During the end of the growing season, while the landscape is in full bloom and lush, landowners are better able to visualize opportunities to develop wildlife habitat, provide visual barriers, and improve aesthetic qualities on their property. These timely observations and some research will provide the necessary information to determine how newly-established trees will impact their property.
Once a landowner has determined the goals for their tree planting project and considered all of the details (location, landscape attributes, species selection, etc.), it may be time to ready the site for seedlings. This is referred to as site preparation (prep) and is just as it sounds: preparing an area to facilitate the planting of seedlings and control any present challenges that would inhibit seedling establishment.
Site prep can be either mechanical (utilizing various types of machinery and implements) or chemical (applying commercially produced herbicides). Mechanical site preparation manipulates the soil and provides short term vegetation control. It loosens soil and incorporates organic matter. It can be used to disturb the planting row or the entire planting area. Plowing, disking, furrowing, and scalping are methods to prepare the seedling bed and mowing reduces the vegetative competition to seedlings. Chemical site preparation, specifically herbicides, impacts current weed populations and can provide future weed control. This allows trees to become established without competition for water, sunlight and nutrients. Chemicals can be applied quickly and are less labor intensive than most mechanical techniques. Both work well and are commonly used together.
The site needs to be analyzed to determine the most effective, cost-efficient site prep methods. This should takes into account soil type, volume and species of existing vegetation, and landowner’s time and financial constraints. It is also important to remember these may change over time. The amount and intensity of the site prep required is determined by the purpose and the vegetation present on the site. For example, open fields with light sand soils may only require minimal mowing to create a welcoming environment for seedlings. However, recently-harvested sites with slash piles and thickets of undesirable brambles or trees may require intense chemical and mechanical preparation. Regardless, a successful tree planting can be determined by how well the site is prepared for planting.
Site prep requires time, effort and cost, so it is important to get advice from professionals. Both chemical and mechanical can be effective, but each has limitations. Mechanical site prep includes the use of specialized equipment that may be costly. It may increase soil compaction, erosion and seed bank development may result from poorly timed or excessive site preparation. Mechanical techniques usually only provide short term relief from vegetation translating into more treatments. Chemical prep utilizes pesticides, some of which can have negative environmental impacts if improperly stored, applied, or disposed. Application requires specific equipment and knowledge of application rates. This can be challenging, especially for the inexperienced, and may require professional assistance. Effectiveness is dramatically impacted by weather conditions, soil texture and the stage of weed development. For landowners that would rather seek the help of a professional, visit http://dnr.wi.gov/topic/TreePlanting/sitePrepVendors.asp for a list of individuals that may be able to assist. More information on herbicides may also be found at http://dnr.wi.gov/topic/ForestHealth/Herbicides.html
However, even with these challenges, landowners who follow through on site prep tend to have better seedling survival and performance. Seedlings, given the opportunity to grow and flourish, will soon capture a site and provide the future forest products, wildlife habitat, erosion control and aesthetics the original planters desired.
Written by Jeremiah Auer, Wisconsin DNR forest regeneration specialist, (715) 459-1999, Jeremiah.Auer@wisconsin.gov