Critical for dairy cattle rations Necessary for phosphorous (P) uptake Need yield maximized for feed production and maximum P uptake
Examination of 26 different studies showed decrease in yield Corn yield reduced 5 to 15% for corn following corn compared to the first year corn www.agecon.purdue.edu/pdf/Cr op_Rotation_Lit_Review.pdf
Choose the corn seed hybrid most desired for your farm – considering soil, rotations, insect/disease pressures, residues, manure or compost applications, emergence concerns etc. http://corn.agronomy.wisc.edu/HT/200 7/Text.htm has corn hybrid performance for grain and silage in Wisconsin http://corn.agronomy.wisc.edu/HT/200 7/Text.htm
Dale Baker has variety trial on corn grain from Kimberly Then look at cost and necessity of seed treatments included on the seed for insect and disease control.
We need to minimize insect and disease concerns to maximize corn yield and P uptake Crop rotation is an effective management tool for reducing hosts for pathogens
Eggs laid in soil during the fall – hatch in spring Larvae feed on corn roots Adults emerge from soil Adults beetles feed on female flowers (silks) and soft kernels
Repeated efforts to control rootworm has led to resistance to methyl parathion and carbaryl www.areawiderootworm.info/final_report.pdf www.areawiderootworm.info/final_report.pdf Crop rotation is an important option to prevent large rootworm infestations Consider chemical and transgenic control when it is economically required
HostEnvironment Pathogen Disease Risk of disease severity higher with continuous corn, but weather conditions in-season still affect disease severity
Long term buildup of soil born pathogens can reduce corn stands, vigor, yield, plus decrease nutrient uptake potential. Pathogens survive on corn residues and/or in the soil. Crop rotation beneficial to break the cycle
Increased corn acreage = more stubble, roots, and crowns = potential for increasing Fusarium graminearum, which causes primarily scab (head blight) in wheat and barley, stalk and ear rot of corn
Gibberella ear rot is caused by the fungus Gibberella aeae, also known as Fusarium graminearum. It usually appears at the ear tip and is red or pink. A vomitoxin can be produced that causes vomiting in monogastrics.
To stop, look, and carefully evaluate the best corn hybrid and insect/disease control for your farm Practice good crop rotation to minimize costs and mgmt. intensity for corn production in Idaho, while maximizing P uptake Keep accurate records when using transgenic seed and chemicals
Crop% P% H 2 OYield lb P Removed Canola seed 0.44102000 lb/A8 Peas0.38132000 lb/A7 Beans0.604028 cwt/A10 Potatoes0.2080500 cwt/A20 Sugar beets 0.137735 tons/A21 P Content and Removal with Crops Information from National Research Council (NRC) with modifications for Idaho where data is available from Dr. Brad Brown, UI in Parma
Crop% P%H 2 OYield lb P Removed Wheat grain 0.4310120 bu/A28 Barley grain 0.3910120 bu/A20 Oat grain0.4010160 bu/A18 Corn grain 0.3015.5180 bu/A25 Corn silage 0.266730 tons/A51 P Content and Removal with Crops Information from NRC with modifications for Idaho where data is available from Dr. Brad Brown, UI in Parma
Soil Test P Decline John Brown's annual corn removes 36 lb P per acre. For his soil, the soil test declines 1 ppm for every 12 lb of P removed each year. His manured field has a soil test P value of 84 ppm. How many years will it take with his current cropping system to lower soil test P to 40 ppm based just on the crop P removal with no additional P applied?
Soil Test P Decline Question STP change in one year 36 lb P a year / (12 lb P/ppm) = 3 ppm P Difference in ppm P 84 ppm - 40 ppm = 44 ppm Years to change STP 44 ppm 44 ppm / 3 ppm = 14.6 years
Predicted Soil Test P Increase A new dairy wants to apply composted manure at the rate of 10 tons per acre annually to a field. The compost is 70% dry matter and 0.92% P (dwt basis). Initial soil test P for the field is 20 ppm. He can remove 37 lb P annually with corn silage but is wondering about a double cropping system that would remove 55 lb P per acre annually. Assume soil test P changes 1 ppm for every 12 lb P applied per acre. How many years for STP to reach 40 ppm P?
Predicted Soil Test P Increase Question Net P added per acre? 10 tons x 2000 lb per ton = 20,000 lb 20,000 lb x 0.70 = 14,000 lb dry matter 14,000 lb x 0.0092 = 128.8 lb compost P per acre 128.8 lb P added - 37 lb P removed = 91.8 lb P = net P gained annually with single crop corn 128.8 lb P added - 55 lb P removed = 73.8 lb P gained annually with double cropping
Predicted Soil Test P Increase Question Soil test P change? 40 ppm P - 20 ppm P = 20 ppm P Annual soil test change 91.8 lb net P added/ (12 lb P/ppm) = 7.65 ppm 73.5 lb net P added/ (12 lb P/ppm) = 6.125 ppm Time required? 20 ppm P change / 7.65 = 2.6 yrs with SC 20 ppm P change / 6.125 = 3.26 yrs with DC
Hauling hay from east Idaho here and exporting compost back High fertilizer prices making the export farther away more economical High quality compost marketed for organic producers Lime, struvite cystalization, anaerobic digesters, nursery industry – continue the quest for ways to export P!
Produced by mold fungi – Aspergillus falvus and Aspergillus parasiticus Aflatoxins are harmful or fatal to livestock and are considered carcinogenic No aflatoxins allowed for milk from dairies See Aflatoxins in Corn, PM1800 Iowa State University, for sampling procedures and control methods
Highly effective compounds like the triazoles and Qol fungicides (e.g. strobilurins) with specific modes of action developed These affect one specific site in one metabolic pathway of fungus Fungi only have one barrier to overcome
FRAC = Fungicide Resistance Action Committee Goal is to provide fungicide resistance mgmt guidelines to prolong effectiveness of “at risk” fungicides.
Look on label for group number-easier to alternate chemistry M is when a fungicide acts onmultiple sites and resistance is low
ProductRate (fl oz/acre)REI (hours)PHI (days) Headline6-1212 a 7 Quadris6-15.54a4a 7 Quilt7-1424 a After brown silk Statego7-1224 a After silking Tilt2-424 a After silking a REI is 7 days for bare-hand detasseling activity *Headline and Quadris are strobilurin fungicides *Considered “high risk” for fungicide resistance *May result in yield increases, even in supposed absence of any disease pressure, in short term *Exercise caution-use only when required to minimize selection of fungicide-resistant strains of fungal pathogens. *http://www.ipm.iastate.edu/ipm/icm/node/2529/print