Corn Silage Evaluation By : Dan Steward

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1 Main Office: 5242 Curtis Road, Warsaw NY Randolph Office: 91 Jamestown Street, Randolph NY Corn Silage Evaluation By : Dan Steward September 1, 2012 The time is here to evaluate your corn crop for the harvest season. The best way to do that is to take a quick tour of all of your corn fields on the same day to get a snapshot of their maturity. Knowing that you will always have variability within a field, you should pick a representative area and evaluate the kernel maturity. Although, there are a number of different ways to describe the maturity of a kernel, if you are consistent in how you classify an ear, you can get a good relative ranking. It never hurts to estimate the time until the corn will reach ½ milkline, as well. The classifications and estimated times I use is delineated in the table below. Once you have a snapshot of maturity, you can then monitor certain fields every few days to get an idea of how the crop is progressing. Should Half Milk Line be your Goal? Kernel Stage Estimated time till ½ milkline Blister 4 weeks + Milk 3-4 weeks Dough 3 weeks + Early Dent Half Dent Full Dent Early Milkline ¼ Milkline ½ Milkline days Two weeks days 7-10 days 5-7 days Harvest Now! Yes! With high corn meal prices, we want as much grain in our silage as possible. At ½ milkline, you are capturing almost 100% of the potential yield of the corn, and most of the starch potential. If allowed to mature past this stage you would not gain any more whole plant yield, even though you would gain more starch. Additionally, stover digestibility would decrease, kernels might become too hard for the cow to digest and the silage might become too dry to pack. Sure, kernel stage is only a rough indicator of kernel moisture, corn at ½ milkline might vary from 30% to 40% DM depending on precipitation and plant health. But assuming you pack it properly, corn will have no problems fermenting over this range of moisture. Over the next couple of weeks, we will be helping you assess the moisture of your corn at different stages by using portable chipper/shredders. As an operator, you should know your capacity to harvest corn pretty well. Look at your snapshot of corn maturities and moistures, and the estimated days till harvest and pick a starting point that makes sense. If the vast majority of your corn is going to be at ½ milkline in about a week and it will take three weeks at a minimum to harvest it all, don t wait a week to start. A lot of it will get too dry. Conversely, if it only takes four days for your custom operator to harvest your corn and the majority of it is at 70% with no milkline, wait a while. There is no justification for chopping immature corn this year, unless you are out of silage. After all, it s only the end of August!

2 Page 2 FALL CUTTING MANAGEMENT OF GRASS By: Dan Steward We pay a lot of attention to our management of alfalfa fields to help them persist, (see article on page 4) but it is not often that we think about our grass stands. The developing tightness of hay forage supplies is dictating that we have to change. Many growers have been disappointed in their grass hay yields the last number of years. Of course grass does not grow without rain; however there are strong indications that poor yields on some fields aren t just the result of lack of moisture. Something about the way we are managing grasses is causing a decline in yields. (There is actually a Mid-Atlantic Orchardgrass Task Force that is made up of professors who are trying to identify the specific causes of declining yields.) While investigating how we should manage grass in the fall, I came across an excellent abstract titled Management of Cool-Season Grasses for Hay Production and Quality by professors Steven C. Fransen and Thomas C. Griggs. In their abstract they propose a different approach to grass hay management. The following is taken directly from their writings. Most grass hay growers have taken the approach that the grass is always going to be there. Hey, it's just grass, no big deal. Stands are replanted with hopes of greater production, but low yields return. Growers may perceive that this is a cycle within grasses that cannot be broken. Through intensive research of harvesting and root sampling various cool-season grasses a different approach is proposed to reverse inherently low grass hay yields. It all starts with understanding what occurs below ground as much as what we harvest. Unlike alfalfa that stores its carbohydrates in the crown and taproots, cool-season grasses store most of their carbohydrates in the bottom 3 to 4 inches of stubble. Actually very few carbohydrates are stored in the fibrous root system. Figure 1, adapted from Fransen et. al. (2003), depicts dynamics of above and below ground growth cycles for about a dozen cool-season grasses grown in WA State. This is the basis of their forage calendar, which starts in September, the real beginning of the cool-season grass growth cycle. During September and October the following years' seedhead meristems are established. Additionally, this is also marks the first generation of new grass roots. The previous few months of summer the grass roots were dying and being shed by the plants. These grasses will again shed roots during winter when the top is either dormant or covered in snow. In the spring the roots will start growing 1 to 3 weeks before you can actually see new green growth. Spring root production will be delayed and reduced if livestock are allowed to graze hay fields in late winter or early spring when spring root production begins. The spring rooting period extends longer than in the fall but most coolseason hay-type grasses will not produce new seedhead tillers at this time. Following the summer solstice these plants will again shed their roots until fall. It is easy to follow the pattern described here by simply digging the grasses, washing the soil from the roots, and observing if the roots are white (alive and healthy) or tanbrown-black (dying to dead). Most grass hay growers permit livestock to graze the fields down to nearly soil level in the fall. This only eliminates the major carbohydrate storage tissue -- the bottom 3 to 4 inches of stubble -- that is needed to continually feed the newly established fall seedheads. By removing this stubble the grass must draw from its already meager root reserves for winter survival. This always delays spring green up from several weeks to a month. If you must graze the hay field in the fall, you can increase cool season grass hay production by not allowing animals to graze lower than 3 or 4 inches from the soil surface.

3 Page 3 Cont. from pg. 2 In addition, maintain excellent soil fertility - especially phosphorus and potassium - as the grass enters the critical fall regrowth period. In the spring allow the new root system to become well established if the goal is to produce heavy, first cutting yields. Regrowth cuttings are also dependent upon maintaining proper stubble height when the grass is undergoing great stress during summer root shedding. Never cut coolseason grass hay fields lower than 3 inches! To maintain healthy, productive, and dense grass stands requires careful attention to increasing grass roots and maintaining stubble. Decreasing grass rooting dynamics will delay spring green up, decrease first cutting and total yield, reduce nutrient and water uptake, increase weed invasion, increase environmental stress on the plants, and support the same excuses for low yields and poor quality used for years. Alfalfa hay growers learned fall management is critical to plant survival and generous yields, and this is also very true for cool-season grasses. Three Practices Critical to Increasing the Long Term Productivity of Your Grass Stands: 1. Don t take a late cutting. September and October are critical for forming next year s tillers. A cutting taken later than mid-september will help you feed your cows this winter, but will result in less yield next year. 2. Leave at least 3-4 of stubble when mowing. Carbohydrates for regrowth are stored in those bottom 3-4 of growth, not the root system. 3. Maintain soil fertility by applying more than just Nitrogen. We have gotten into the habit of just applying nitrogen on grass. High nitrogen rates and low potassium will result in poorer winter survival and higher susceptibility to diseases. Unfortunately, grass will remove just as much potassium as alfalfa. It will also take up more than it needs for optimum growth. If you are seeing very low or low soil test K and/or forage samples with K concentration below 1.7%, you are probably hurting your stands. Fall, not spring, is the best time to apply potassium. Obviously, manure is a great source of N, P, and K.

4 Page 4 Considerations for Fall Alfalfa Harvest By Dave Wiggers The Summer of 2012 has been a challenging time for farmers and won t be forgotten anytime soon. Much of the alfalfa crop has been affected by the spring frosts, and the drought, leaving many farms short on hay. A late September or early October cutting of alfalfa may be a necessity this year, but there are a few things to consider when evaluating which fields to harvest and when to harvest them. Alfalfa stores carbohydrates in the roots during the fall for winter survival and initial plant growth the following year. A plant will use the carbohydrates for regrowth after being mowed, so it is important to harvest fall alfalfa with this in mind. Alfalfa stands should be managed so that the root reserves are maximized before the first killing frost. A rest period of around 5 weeks before the last cutting would allow enough time for this to occur. The worst-case scenario would be taking a fall cutting on short rest (<30 days from previous cutting) and then having 6-8 inches of regrowth before the killing frost. Another option would be to harvest alfalfa after the killing frost. This would prevent any loss of carbohydrates to regrowth. The drawback is the risk of frost heaving would increase. Young alfalfa stands with high fertility are less susceptible to winter injury and can be managed more aggressively. The same can be said for fields being rotated the following spring. The Penn State University table to the right can be used to determine the risk of winter injury from a fall cutting of alfalfa. Next years alfalfa crop can get off to a good start based on management practices used during the next few months. Here are two examples using the table: Example 1-2 nd year stand -high disease resistance and FD = 3 -high potash and well drained -four cuttings by Sept. 1 and additional cut after killing frost with < 6 in. stubble Score= 11 (moderate risk of winter injury) Example 2-5 th year stand -high disease resistance and FD = 3 -low potash and moderately well drained -four cuttings by Sept. 1 and additional cut after killing frost with < 6 in. stubble Score= 18 (high risk of winter injury)

5 Page 5 Spreader Calibration By Rhonda Lindquist Now is the time to start thinking about next year s crop rotations and plan for your fall and winter manure applications. With the increasing cost of fertilizer and the ever changing environmental regulations, getting the most value from the manure on your farm while minimizing the potential for water quality concerns requires careful management of the manure resource. While good manure management begins with soil testing, manure analysis, and planning; actually spreading the manure is where the rubber hits the roads. An often overlooked, yet vital (and for CAFO s, legally required) part of implementing a plan is the calibration of your manure spreaders. Spreader calibration can save you money on fertilizer as well as protect the environment by minimizing nitrogen loss to ground water and phosphorus to surface water. Determining the agronomic rate of manure application is important for nutrient management planning and the only way to know what rate of manure you are applying is to calibrate your spreader. To get started, you will need to have reliable estimates of both amount applied and area covered. Box-type solid or semi-solid spreaders should be weighed to adjust for variations in moisture and fullness of a typical load of manure from the rated capacity. The Crop Management Association has portable scales that can be used to weigh your tractor and spreader so that you know the actual amount of manure being applied. These scales work pretty well with most box or V-spreaders. Unfortunately, it is difficult, and in many cases impossible, to weigh most liquid tanks due to the size of their flotation tires. Instead, an adjustment to the designed capacity should be made to account for manure foaming and/or solids build-up. The next step is to determine the area covered by one spreader load by measuring the width of one spreader pass and multiplying by the distance traveled to empty the spreader. The manure application rate can then be determined by dividing the amount applied by the area covered. Don t overlook this valuable nutrient tool for maximizing the efficient use of available manure nutrients. Manure spreader calibration is essential when trying to achieve the desired agronomic rates to attain optimum crop growth and protect the environment. BOARD MEMBERS President Vice President Secretary/Treasurer Eric Dziedzic Donn Branton Betty Nichols Ben Atwater Kevin Nedrow John Reynolds Tim Wittmeyer

6 Page 6 CAFO News By Rhonda Lindquist At the first New York State Yogurt summit, held in August, Governor Cuomo announced that the State is proposing to increase the CAFO threshold number from 200 to 300 (for mature dairy cattle). This would allow dairy farms to expand to 300 cows without having to be regulated by the State. While we feel very encouraged by this news, we should not be jumping out of our chairs yet in jubilation. We must remember that this is only a proposal and there have been no changes made in the law at this point The process to change the law and write a new permit is very lengthy. Farms should continue to operate their facilities according to the rules and regulations of the permit they are currently under. We will continue to monitor the situation and keep you apprised of any changes. As we all know too well, the State does not always operate as swiftly as we would like them to. If you have any questions, please do not hesitate to contact your farmstead planner. Are You Planning to Incorporate Intensive Wheat Management In Your Operation? This year we saw some of our best wheat yields ever with many fields averaging more than 100 bushels per acre. This is due in large part to the implementation of an Intensive Wheat Management System. While this involves several steps to be performed in the spring, proper planning now is critical. There are three components involved in managing wheat that must be addressed this fall. If you are considering implementing this system, speak with your crop consultant to determine a proper fertilizer program. He can also assist you with variety selection by reviewing yield and standability data from research trials. Once your soil is prepared and your variety selected, the next critical step is seeding rate. An application of live wheat seeds per acre based on planting date is utilized instead of planting a set rate in bushels per acre. The seed ranges from 9,500 to 14,000 seeds per pound, with an average of approximately 11,750. Too thick of a stand can cause wheat to lodge while a thin stand means yield loss. The following table displays optimum seeding rates. Live seeds per acre in millions Soil Conditions Sept 15 Sept 25 Oct 5 Oct 15 Good 1.33 mill 1.45 mill 1.57 mill 1.69 mill Average 1.45 mill 1.57 mill 1.69 mill 1.8 mill Poor 1.57 mill 1.69 mill 1.8 mill 1.93 mill Increased wheat yield next year is contingent on what you do now. Speak with your consultant and get sowing!