Chapter 15 Tillage: working the soil to provide a good environment for seed placement, germination, and crop growth

3 goals for Tillage 1. Weed Control Before Planting Kill weeds weakens perennials After Planting destroys weeds covers seedlings

2. Alteration of Physical Soil Conditions Structure, Moisture, and Temperature Stirs and loosens soil improves aeration creates suitable medium for growth may breakup soil compaction

2. Alteration of Physical Soil Conditions Causes long term decline in Structure loss of organic matter crushes soil aggregates Moisture and Temperature tilled warms earlier, causes earlier seeding and better germination

Crop Residue Management amount depends on crop 8500 lbs/acre off of 150 bu corn 5600lbs/acre off of 100 bu corn

Crop Residue Management amount depends on type of tillage Plowing 5% Field Cultivator 80% Chisel 80% Disc 6” 25%, 3” 50% Harrow 65%

Seedbed Preparation Culmination of all 3 aspects Meets requirements for seed to grow moisture, temperature aerated, yet compacted free of clods Type of seed determines how smooth you need seedbed

Conventional Tillage Primary Tillage Breaks up soil and buries crop residue inverting equipment Plowing, time consuming, no residue Discing

Conventional Tillage Secondary Tillage Produces fine seedbed that breaks up into smaller chunks mixing implements

Conservation Tillage Leaves 30% of residue reduces erosion by 40-50% reduced tillage fewer trips, compaction less

Conservation Tillage Mulch Till Chisel, Secondary, 30-50% residue Strip Till No Primary tillage planter tills band of soil and plants bares 1/3 of soil 50% residue

Conservation Tillage Ridge Till plants cleaned strip seed planted on ridge 2/3 residue

Conservation Tillage No Till specialized planters 90% untouched ground Herbicides used to control weeds rather than tillage

Differences between Conservation and Conventional Yields slightly lower in Conservation Equipment conservation needs specialized, but fewer Fertility Conservation remains moist longer, N needs to be deeper incorporated in Conservation PH may be higher

Drawbacks to Conservation Management Adapted for select soils Perennials can be a problem Compaction in No Till can be a problem PH lowers Use of herbicides

Cropping Systems 3 Different ways to decide what to plant

Plant the Market Plant what the market wants you to, highest price

Suit to Operation Plant what you will use in ag operation

Crop Rotation 1.Continuous Cropping grows same crop every year yields decline after several years

Crop Rotation Disadvantages planting less profitable crops do not use crops that you need to plant

Crop Rotation Advantages Control disease and insects Control weeds allelopathy: chemical emitted by a crop that kills weeds in next crop supplies N Improves O.M. Reduces erosion

Dryland Farming No irrigation Summer Fallow left fallow for 1 crop season control weeds and crop on field 25% of rain will be stored in ground

Dryland Farming 3 Problems 1. Wind erosion 2. Decline in O.M. 3. Saline Seeps

Dryland Farming Saline Seeps: Deep rock layer stops water and pushes it downhill water carries salt with it comes out at low spots of hill water evaporates leaving salt behind

Dryland Farming Avoid saline seeps by moving the water before it can evaporate

Rangeland Four SCS ranks 1. Excellent 2. Good 3. Fair 4. Poor

Rangeland Things to do to make rangeland more productive 1. Control grazing 2. Fertilize 3. Seed out new plants

Organic Farming No inorganic fertilizers or synthetic pesticides are used Usually use rotation w/legumes to supply N Rely on tillage and cultivation rotary hoe

Organic Farming Results of O.F. better bean and oats yield erosion is reduced use 1/3 of energy sell to regular markets some utilize only part organic

LISA Low Input Sustainable Agriculture Maximizes profits by reducing costs Minimizes off farm inputs