HONESDALE (Wayne Co.) The question of fall fertilization of forage crops is most often related to concerns about winter survival of perennial forages. While fall fertilization can have an impact on winter survival there are many other factors that influence winter survival, including the overall nutritional management of the crop, harvest practices throughout the year, weather conditions, and varieties just to name a few. The following is a focus only on the nutritional factors. For new seedings the key to winter survival is to have a healthy, well established plant going into the first winter. Having soil test levels at least in the optimum range for pH, pho sphorus, and potassium before estab ishment is critical. While all of these fertility factors are important, it has been shown that good levels of pho sphorus will promote vigorous root growth in the new seeding. A larger, more well established root system will be more resistant to heaving, which is a major cause of winter stand loss, especially in new seedings. A fall Maximize YjpJ^jPotential When it comes to improving Relative Feed Value and maximizing the Crude Protein in hay, nothing outperforms the New Idea 9 ’ 5209 Disc Mower Conditioner Its high-speed disc cutterbar glides through fields with ease, even in extreme conditions And the unique Ti-Cor® Conditioning Rolls gently condition the stems, speeding drydown Fall Fertilization Of Forage Crops application of fertilizer to a new seed ing cannot make up for the lack of good fertility at planting and resulting small root system. Once a forage crop is established, the fertility program should focus on maintenance of good fertility levels in the soil for the life of the forage stand. The most important part of the mainte nance program is regular soil testing to determine the need for lime, pho sphorus, or potassium to replace the large amount of nutrients removed in the forage. On grasses nitrogen will also be an important part of the main tenance fertility program. For legumes and grasses, potassium seems to be the most critical nutrient for winter survi val. Potassium, being a salt, lowers the freezing point of cells just like apply ing salt to a road lowers the tempera ture where the water on the road will freeze. Also, potassium influences the levels of soluble sugars in the cell sap. These sugars act as an antifreeze in the plant cells enabling them to withstand lower temperatures without freeziung. The timing of phosphorus and potassium applications for foragesa will depend on the situation. When the The 5209’s reliable design keeps you mowing and conditioning year after year With the segmented cutterbar dnveshaft, a New Idea innovation, the cutterbar is truly mod ular, which makes for easy maintenance To see the disc mower conditioner that'll exceed your expectations not your budget, visit your AGCO„ New Idea dealer today New Idea I ABCO BOUT FOR THE BOTTOM lIHE Foraging Around, Lancaster Fanning, Saturday, November 1, 1997—Page soil test levels are in the optimum range and the recommendations are low, the timing of fertilizer applica tion is not critical. These low recom mendations on an optimum testing soil are only to replace what the crop will remove so that the test level is still in the optimum range going into the following eason. Fertilizer can be applied after one of the cuttings or in the fall.'There will be no advantage to splitting the fertilizer application in this situation. Given a choice betwen applying the fertilizer during the sea son or in the fall, fall application may provide a very slight insurance effect, but this is not a major consideration. Where high rates of fertilizer are recommended there may be an advan tage to splitting the application some after first cutting and the balance in the fall. Many plants will take up potassium whether they need it or not. This is called luxury consumption. If all of the fertilizer is applied at one time, the next cutting may take up more than it needs leaving the crop short later on. By splitting the applica tions the efficiency of potassium use will be improved because there will be less luxury consumption. Also, as noted before, if the soil test levels are low enough to result in a large recotn menation, particularly for potassium, applying some of the fertilizer in the fall before the plants are dormant may improve winter survival. On forage grasses nitrogen is another consideration. Nitrogen should be applied to grasses in the spring and after each cutting, except the last cutting in the fall. The rate should be based on the expected yield of the following cutting. Applying nit rogen in the fall for use by the crop the following spring is not recommended. Another important consideration for nitrogen fertilization of grasses is the balance between nitrogen and potas sium. Nitrogen applied in the fall on soils with low potassium levels can increase winter kill of grasses over where no fertilizer is applied. Thus, soil tsting and applying a balanced fer tility program is important. There are no special considerations for nutrient sources used for fall fertil ization of forages. All of the standard fertilizer materials are acceptable. Manure is also a source of nutrients. See Your AGCO - New Idea Dealer Listed Below. Delaware Georgetown Baxlei Fauns Maryland Dayton I D Mullimx Linehoro Weil/ I .uni f quipmcnl Pennsylvania liechtehville ■Millci Fi|Uipmenl Bethel Zimmciman s I aim Semee Bloomsburg William F Wcllnci Carlisle Carlisle Farm Sei vice Chamhersburg Chambershurg Farm Service Cochranville Slolt/lus Farm Service Cress on Hines Equipment Greencastle Meyers Implements Klingerstown Stanley’s Farm Service Lebanon Umbergers of Fontana Mercer Ralph W Kyle Mifflinburg B, S&B Repair Oakland Milk Peoples Sales & Service Quakertown C J Wonsidler Quarryville A L Herr Somerset Lincoln Supply 197 The phosphorus and potassium in manure can be considered equivalent to fertilizer phosphorus' and potassium in their efect for building soil fertility. The availa bility of nitrogen will range form 20 to 50% depending on how soon alter application it is soaked into the soil by rainfall. The sooner it gets rain the better. Manure is not generally recom mended for legumes because the nitrogen in the manure is wasted and ther is the potential for some adverse effects from manure application to legumes. If manure must be applied to a legume, fall is prob ably the best time to apply it to minimize the potential negative effects. While having good fertility levels for a forage crop in the fall is critical for optimum production, fall fertil ization is only one part of the manage ment system to achieve this. Opti mum soil test levels should bife-established prior to seeding and a maintenance fertiliza tion program based on regular soil testing are the foundation of good nutrient man agement of forages. Douglas Beegle Penn State Agro- nomist