Woody Vegetation (Trees) Establishment on Upland Sites

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1 Technical Note Woody Vegetation (Trees) Establishment on Upland Sites Introduction This Note provides guidance for the planting of trees to fulfill the woody layer requirement of Alberta s 2010 Reclamation Criteria for Wellsites and Associated Facilities in Forested Lands (the Criteria). The Note discusses both coniferous tree seedlings, and those deciduous trees that will grow from either seed or vegetative cuttings. Planting should be carried out on sites that have been prepared for tree planting. The sites should contain soil friable to sufficient depth to allow tree root penetration, and preferably be rough at surface with a presence of stones and coarse woody debris. This allows microsites for individual seedlings or cuttings to be planted where microclimate and drainage are favorable to survival and growth. Regulatory Context Regulatory context is provided in Section 7 (7.0 through to 7.3) and in Appendix D, of Alberta s 2010 Reclamation Criteria for Wellsites and Associated Facilities for Forested Lands. Recommended Practices Coniferous Trees Seedling Order The Criteria has an expectation of establishing 2000 tree stems per hectare for merchantable trees when planted. Commercially available conifer seedlings (Photo 1) are appropriate for use under this definition.

2 Photo 1: Lodgepole Pine Seedling These seedlings need to be grown with seed from the appropriate seed zone, or with an approved variance from the Alberta Sustainable Resource Development Department (ASRD). ASRD can also advise the names and locations of forest seedling nurseries that provide seedlings to the market seedlings per hectare from a specific seed zone for a typical wellsite means a very small order for a commercial seedling nursery. Consider grouping sites to increase order size and gain economies of scale. Alternatively, contact the forest company in the area where the site exists. Forest companies normally place large orders for seedlings and you may be able to purchase appropriate seedlings through them. Allow as much lead time as you possibly can, as forest comapany orders can be six months to two years in advance of their delivery date. The forest company may have appropriate conifer seed for sale if that option is preferred. Choose the species of seedling to match the site conditions. Generally, the surrounding vegetation will indicate what conifers grow in the area. Pine requires full sunlight to do well, and is more tolerant of poor nutrient and/or frost prone sites. Frost prone means that there are low spots on the site where cold air will collect because it cannot flow (think of air as a liquid) offsite. Spruce tolerates shade and will withstand snow press from nearby vegetation that is taller than the seedling the first years after the plant. It is less tolerant of drought conditions than pine.

3 Choose size of seedling to match site conditions. Seedling size is usually referred to in terms of the brand of container the nursery uses. However, if you think of seedlings as small, medium and large, that will suffice. Generally use a middle sized, robust seedling to overcome any competitive vegetation that might be on site. If drought conditions are expected. reduce the seedling size to small in order to limit excessive transpiration. Seedlings planted in Alberta in May and June have been grown, over wintered in a frozen condition, and will break bud and grow in the current summer. Trees planted in July have been grown over the winter, forced into dormancy, and will grow again the following summer. Seedling Delivery Seedlings should be delivered in a timely manner. Once lifted from the nursery, seedlings should be planted as soon as possible. Discuss delivery timing with the nursery or forest company and schedule planting accordingly. While being transported from the nursery and stored on site, seedlings should be kept cool and moist. If seedlings are to be left stored for more than a few hours, open the seedling boxes in shade and ensure the root plugs are moist. In cases where shade is not available, cover the seedling boxes with reflective tarps (Photo 2). Photo 2: Seedling Boxes Protected with a Reflective Tarp Alternately, the forest company will normally be transporting seedlings in refrigerated vans, and can be requested to deliver seedlings to a central point for distribution. Final delivery to site can be done with pick-up truck or ATV depending on access conditions. For remote situations, consider that most helicopter firms are familiar with the slinging of seedling boxes.

4 In all cases, minimize rough handling of seedlings. Physiological stress and physical damage are cumulative in effect and will affect growth. Planting Workforce Photo 3: Tree Planter on a Wellsite Seedlings are normally planted by hand (Photo 3) on the site. Forest companies employ tree planting contractors who do this, and they are the most likely source of trained labor to complete the job. They may be hired through the forest company, or contracted directly. Ensure that the contractor realizes that reclamation planting involves smaller crews moving to multiple sites. This requires a slightly different management process than larger crews working in a large harvest block for a forest company. Planting contractors have safety plans and processes; however reclamation planting may have different hazards and safety requirements that need to be discussed at contract time. Pay for tree planting can be either piece rate or by the hour. Discuss with the contractor. Planting Microsite Selection The first priority in planting is to ensure that each tree is planted in the best available microsite, within the limitations of spacing requirements. Spacing between seedlings is determined as the square root of the amount of square meters the seedling occupies, if the 2000 seedlings are planted evenly over the hectare. A hectare contains 10,000 square meters; when divided by the 2000 seedlings, then each seedling occupies 5 square meters. The square root of 5 is 2.2 meters, the spacing between seedlings.

5 It is more important to choose a better microsite than to hit the exact spacing. Microsite will have a far greater effect on survival and growth, so allow some tolerance, allowing the planter to step out of the spacing grid. An acceptable microsite will provide moisture, nutrients, light, and warmth to the seedling. This means planting a seedling mid-slope at the micro level, where roots will not dry out or be flooded. Planting next to an obstacle such as a rock, a lump of hard soil, or a piece of coarse woody debris provides warmth and some frost protection from radiated heat at night. Obstacles also reduce drying air currents at the micro level. Seedling Planting At the chosen microsite, the seedling needs to be planted correctly. This involves paying attention to the following requirements. The planting hole needs to be deep enough that the seedling is planted at least to its original growing depth in the nursery, as indicated by the soil line on the stem. Err on the side of planting deep rather than shallow. Hole depth also allows roots to hang straight down. If the hole is too shallow, the roots will bend up, resulting in a condition known as J rooting, an unacceptable situation. After placing the seedling in the hole, the planter needs to backfill the hole with appropriate material, normally the surrounding soil. Seedling should be upright and firmly placed, with no air pockets around the roots. These requirements can be checked visually or by feel. J roots and air pockets can be judged by digging up a sample of seedlings to check, and then replanting the seedling. Firmness can be checked by pulling on two needles at the top of the seedling. The needles should come loose before the seedling comes out of the ground. Examine the seedlings for upright position and broken tops. Some tolerance should be allowed the planter as to quality of the planting. Forestry companies normally allow a 5 percent tolerance, but discuss this with the contractor. Exceeding tolerances normally results in a replant. A reduction in planter pay is possible, but well planted trees are a better choice, even if it needs to be done twice. Deciduous Trees The two most common native deciduous trees that used for reclamation in Alberta are willow and balsam poplar. They can be planted in the ground directly, or can be first rooted in a nursery container and planted much like conifer seedlings.

6 A third tree, the aspen, sprouts from roots rather than cuttings and is therefore quite difficult to utilize. However, nurseries can produce aspen seedlings to some extent and they are becoming increasingly available. If utilized, follow the practices for conifer seedlings. Cuttings Supply If choosing to utilize nursery containers, discuss the timing and delivery of cuttings with the nursery. If choosing a vegetative option, whips should be collected in mid-march to mid-april from oneyear-old growth. This is the most viable part of the plant with respect to new growth. Store whole pieces wrapped in poly, in a freezer or root cellar, preferably with temperatures between minus 3 degrees C to plus 1 C. In late May, a decision will have to be made regarding the best cutting size for site condition. If droughty conditions are expected, a better alternative will be to plant long cuttings (up to a meter long). This ensures that at least part of the cutting will be deep enough to contact subsoil moisture. If moist conditions are expected, then cut the whips into 15 cm cuttings which should have several buds on them. Soak the cuttings in water for two days prior to planting. Planting the Cuttings If planting rooted stock, follow directions for conifer seedlings. Plant the cuttings vertically at the appropriate spacing and ensure that one bud is above the ground line. Planting means simply pushing the cutting into the ground if the soil is soft enough. Otherwise use an implement like a pointed steel rod to make a hole deep enough, and allow the soil to compress back against the cutting. Critical Points Trees will fulfill the requirement for a woody layer of vegetation Native tree species will do well, and in fact are the only option on Alberta public lands at this time. Trees require proper growing or cutting preparation regimes. Proper microsite selection will aid greatly aid in establishment and growth