Laserfiche WebLink
4. The specifications and plans are unclear as to the exact species composition of the <br />prevegetated mats. Also, there is the question of whether or not the prevegetated mats <br />should be the single or multiple species variety. Jim asked for our recommendations in <br />this regard. We are suggesting mixed mats for the tall and short project areas and single <br />species (or low diversity) mats for the stormwater sediment basin area. Although the <br />mixed mats won't necessary adhere to the "short" and "tall" designations on the plans, <br />they tend to be more successful because they are so diverse (and therefore more <br />interesting as well). The mixed flats contain roughly 16 grass/sedge species and 24 <br />flowers species which makes them more adaptable to potentially changing water levels. <br />For the sediment basin we are suggesting either single species or low diversity (not <br />more than 4 species) mats. Emergement vegetation can often be found growing in <br />colonies and therefore we can try and mimic that natural growth pattern. We have not <br />had a lot of luck with pickerel weed; it is a very sensitive plant that will not persist if <br />conditions are not precise. Therefore we are suggesting a variety of emergent species be <br />utilized including arrowhead, soft -stem bulrush, marsh marigold, sweet flag, wild iris <br />and Joe-pye weed. <br />5. The following outline details the recommended materials and procedures as discussed <br />above. The Sod Flat specification below is for the mixed species prevegetated mats that <br />would be installed in the short and tall areas. There is also some general information on <br />maintenance as well. <br />B. Site Preparation: <br />1. The project area shall be fine graded before the seeding work begins (to be done by the <br />general contractor or excavator). <br />2. Where compacted, and where feasible, lightly till the soil to create an open seedbed. <br />3. Harrow or rake the soil to create a firm, smooth seedbed. <br />C. Seed and Seeding: <br />1. Seeding dates shall be in the spring or summer before August 10th or in the fall between <br />September 20`h and freeze-up. <br />2. Once the soil has been prepared, the grass seed will be broadcast throughout the project <br />area. <br />3. A raking will follow to incorporate the seed into the soil. <br />4. Following the raking, flower seed will be hand sown on top of the soil. No additional <br />raking is required. <br />2 <br />