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CITY OF EVERETT STORMWATER MANAGEMENT MANUAL <br /> i <br /> 6. Organic matter is the most apprr-tiate form of"fertilizer" because it provides nuhients <br /> (including niRogen,phosphorus,and potassium)in the least watcr-soluble fortn. A nahual <br /> system typically releases 2 to 10 percent of iu nutrents annually. Chcmical fertilizers have sincc <br /> been fonnulated to simulate what organic matter does nahually. <br /> 7. In general, 10-4-6 N-P-K(nitrogen-phosphcrus-potassiwn)fertilizer cao be used at a rate of <br /> 90 pounds per acre. Slow-release fe[tilizers should always be used because they are more <br /> efficient and have fewer en��ronmental impacts. It is recommeoded that azeas being seeded for <br /> final landscaping conduct soil tests to detecmine the exact type and quantity of fertilizer needed. <br /> This will prevent the over-application of fertilizer. Fertilizer should not be added to the <br /> hydromulch machine and agitated more than 20 minutes before it is to be used. If agitated too <br /> much,the 91ow-release coating is destroyed. <br /> B. There are numerous products availahle on the market that takes the place of chemical fenilizers. <br /> These include several with seaweed extracts that aze beneficial to soil microbes and organisms. If <br /> 16(1 percent cottonseed meal is used as the mulch in hydroseed,chemical fettilizer may iot be <br /> oecessary. Cottonseed meal is a good sourcc of long-term,slow-release,available nihogen. <br /> 9. Hydroseed apPlications shall include a minimum of 1,500 pounds per acre of mulch with <br /> 3 percent tackifier. Mulch may be made up of 100 perccnt: cononseed meal;fibers made ot <br /> wood,recycled cellulose,hemp,and kenaf;compost or blends ofthese. Teckifier shall be plant- <br /> based,such as guar or alpha plantago,or chemical-based such as palyacrylamide or polymers. <br /> Any mulch or tackifier product used shall be installed per manufacturer's instructions. Generally, <br /> mulc6es come io 40 to 50 pound bags.Secd end fertilizar are added at time of application. <br /> 10. Mulch is always required for seeding. Mulch can be applied on top of�he secd or simuttaneously <br /> , by hydroseeding. <br /> 11. On steep slopes,BFM or Mec6anically Banded Fiber Mattix(MBF:d)products should be used. <br /> BFM/MBFM products are applied at a minimum ra�e of 3,000 powds per acre af mulch with <br /> approximately 10 percent tackifier. Application is made so that a minimum of 95 percent so�l <br /> coverage is achieved. Numerous products are available commercially and should be installed per <br /> manufecturer's instruclions. Most pmducts require 24 to 36 hours to cure before a rainfell and <br /> cannot 6e installed on wet or saturatcd soils. Generally,these products come in 40 to 50 pound <br /> bags and include all neccssary ingrcdicnts exccpt for sced and fertilizer, <br /> 12. BPVIs and MBFMs have some advantages over blankcts: <br /> a. No surface preparation required <br /> b. Can be installed via helicopter in remote azeas <br /> c. On slopes stceper than 2.5:1,blankct installers may need to be roped and hamessed for <br /> safcty <br /> d. They are at least$I,000 per acre cheaper installed. <br /> l3. ln most cases,the sheaz strength of blankets is not a factor whcn used on slopes,only when uscd <br /> in channels. BFMs and MBFMs are good altemativcs to blankets in most situations where <br /> vegetatio�establishment is the goal. <br /> a. When mstalling sced via hydrosecding operations,only about one-third of the seed <br /> actually ends up in contact with thc soil surface. This reduce,the ability to cstablish a <br /> good a,tand of�ass quickly. One way to ovcrcomc this is to increase secd quantities by <br /> up to 50 percent. <br /> b. Vegctation eslablishment can also be enhanc^d by dividing the hydromulch operation <br /> into two phases: <br /> Yolume 11—Construction Stormwater Pollution Prevenfion <br /> 3-10 <br />