lec 10 Flashcards
what is a cover crop? what are their purposes?
crop that is grown to protect/improve the soil rather than to be harvested. protects against soil degradation, weeds, pests
also acts as ‘green manures’ which naturally return nutrients to the soil when they die
what is erthanomisces?
problematic fungi that fucks w peas
what is the difference between a shoulder cover crop and a full season cover crop?
shoulder crops are grown after the main crop to prep the soil for next year, while full year crops are grown all year round
why may a livestock farmer keep cover crops?
when the main crop has been harvested, livestock can be released into the fields to feed –> an investment
what are the most common cover crops?
clover #1, but also oats, peas, and hairy vetch
what are the benefits of cover crops?
reducing soil erosion, incr water filtration, suppress pest and weeds, fix N and reduce fertilizer reqs
what is OFCAF?
on farm climate action fund: a fund by government to push cover crops + provide grants for it
what are some various ways to classify cover crops?
- length of life: annual, biennial, perennial
- season: cool or warm season
- winter survivability: over winter (dies in winter, revives in spring), not overwinter (dies in winter)
what is the general formula for a cover crop mixture?
grass + legume + broadleaf/forb
what are some cold season vs warm season legumes?
cold: field pea, faba bean, berseem clover, red clover, alfalfa
warm: cowpeas, soybeans, adzuki beans
what are the best cover crops for saline areas?
barley, sugarbeet, camelina, sorghum
why would someone grow large root cover crops? what are some ex?
big roots manage compact soil well (compact soil is bad)
ex. incl radish, turnip, sugar beet, pasja, mangle
what makes ryegrass a bad cover crop?
allelopathic - exudes shit that prevents plants nearby from germinating when it dies
ryegrass rhymes with DIEgrass
considering summer and winter niche, what should i look for?
summer niche: outstanding performer - C4 grasses with higher growth
winter niche: survivability - rye
what makes storms so bad?
think of a single rain drop and all the potential energy that gets converted to kinetic when it hits a plant. multiply that by the number of raindrops in a rainstorm. remember that plants are more fragile. boom
what are short term vs long term goals of cover crops?
short term: basically anything to do w keeping the soil strong (soil rooting, N fixing, etc)
long term: anything to do w long term survival (biodiversity, pollination, weed management, etc)
how are nitrate leaching and chemical surface runoff bad? how do cover crops combat this?
cover crops take up N and water, reducing nitrate leaching
how are cover crops beneficial internally to the farm?
protects the farm
more organic soil matter, suppresses weeds (less herbicides needed)
how do cover crops affect field capacity and plant available water?
FC: amt of moisture the soil profile can hold
PAW: amt of water in the soil that plants can access
cover crops had higher of both
what are some disadvantages of cover crops?
increased direct costs of planting cover crops, takes more investment to grow everything (reduces net income)
