Lecture 2 - Forage Fertility

Question 1

what happens when you convert marginal annually cropped land to long-term forage cover

Answer 1

improve soil health and fertility

Question 2

what is soil organic matter made of and what does it contribute to

Answer 2

made of carbon, hydrogen, oxygen, nitrogen, sulphur, and phosphorus
It contributes to soil health and fertility

Question 3

t/f: there are significantly higher organic carbon amounts in top 15cm of grass seed-down than in cultivated comparables

Answer 3

t

Question 4

forages build ________ and sequester ____

Answer 4

soil organic matter, C

Question 5

in what mixture of forages is CO2 production the highest and the lowest

Answer 5

highest in pure grass mixtures
lowest in grass mixtures with legumes

Question 6

fertility effects of growing long term forages

Answer 6

-higher N supply rates over time
-Higher N mineralization, especially in alfalfa
- low P supplies

Question 7

what nutrient is typically low in forage fields

Answer 7

P

Question 8

t/f: forages reduce water filtration

Answer 8

f, forages improve it by reducing soil density

Question 9

what is important to remember about fertility in long-term forage stands

Answer 9

• removal of aboveground material removes lots of nutrients
• requires replenishment of nutrients through manure or fertilizer

Question 10

short rotation forage legumes

Answer 10

4yrs of forage legume followed by annual crops

Question 11

what type of legume are the most efficient N fixers

Answer 11

forage legumes like alfalfa

Question 12

what are non-N benefits of forages on the following crops

Answer 12

other nutrients, improved tilth (soil structure), break in pest cycle

Question 13

how is the deep rooting systems of alfalfa beneficial

Answer 13

better water usage
brings up inaccessible nutrients
benefits organic growers

Question 14

mixed stands often respond better to applied _____ than pure grass alone

Answer 14

P

Question 15

what are some nutrient deficiencies that might be present in forage stands

Answer 15

K, P, S, and micronutrient deficiencys

Question 16

more efficient ways to apply N in a forage field

Answer 16

-granular source of ammonium nitrate or ammonium sulfate
-urea with urease inhibitor
-surface dribble banded UAN solution

Question 17

what is the ideal way to apply manure

Answer 17

liquid injection

Question 18

how does solid manure differ from liquid manure

Answer 18

solid manure is slow release and must be placed on surface (reduces nutrient recovery)

Question 19

how is maximum benefit from perennial forage systems obtained

Answer 19

through good fertility management