Name ______________________________

Agronomy 505 Exam II - 1999

1. __________________________ and ____________________________ prevented successful introduction of alfalfa into Georgia when first attempted in 1736.
2. ____________________ found in ______________________ (legume species) precipitate proteins and prevent animals from bloating.
3. __________________________________ is a disease of alfalfa seedlings and established plants that causes taproots to root off and leads to branched taproots on surviving plants.
4. High rates of ________ fertilizer in spring stimulates grass growth leading to low herbage Mg (<0.2% of dry wt.), and cause ____________________________, a disease characterized by twitching, staggering, convulsions and death.
5. Moldy sweetclover hay contains high levels of ______________________ that can cause uncontrolled bleeding.
6. __________________________ migrate from TX and LA to IN each May to attack alfalfa.
7. Four classes of seed exist within the Foundation Seed Stock project. Farmers purchase the class referred to as __________________________ seed.
8. Application of N fertilizer to legumes at seeding will delay formation of __________________ on roots, and could increase competition from __________________________.
9. ______________________ and _____________________ are two ways to control competition from grass when no-till (inter)seeding a legume into a pasture.

1. ___________________________ is pubescent providing resistance to certain insects.
2. __________________________ has stolons.
3. Few stems of _________________________ elongate during growth resulting in relatively high forage quality.
4. __________________________ is the best forage legume in wet soils.
5. The fragile nature of dry tissues of ________________________ makes it a poor choice for hay if seeded alone.
6. __________________________ has both yellow and purple flowering types.
7. __________________________ has the highest IVDMD because only leaves and petioles are grazed.
8. The mammoth form of ____________________ is a one-cut forage often used as a green manure crop.
9. The intermediate form of ___________________ is used as a winter annual in the southern USA.
10. Winter kill is a serious problem if ____________________ plants are allowed to flower profusely in the seeding year.
11. The narrow leaf form of ________________________ is known for having good seedling vigor.
12. ______________________ originated in Sweden.
13. Powdery mildew often affects __________________________.
14. The taproot of ________________________________ lives only 12 to 18 months.
15. _________________________ has the best seedling vigor of the legumes we've discussed.
16. _________________________ cultivars with glandular hairs tolerate leafhoppers.
17. Because of its very small seed size _____________________ must be seeded no deeper than 1/2 inch.
18. Because of its deep taproot, _________________________ is the legume best suited for dry locations.
19. Frost seeding is best done with _______________________.

1. Ruminant nutritionists recommend the following percentages of NDF, ADF, and CP for high-performing ruminant livestock.

1. 5, 10, 20
2. 10, 20, 30
3. 40, 30, 20
4. 30, 20, 10
5. 20, 15, 10

1. A disease resistance rating for alfalfa of HR means that at least ______% of the plants are resistant to the pathogen.

1. 99
2. 95
3. 90
4. 75
5. 51

1. This insect pest feeds on the surface of roots thereby allowing pathogens to invade taproots.

1. clover root curculio
2. clover nodule midge
3. clover root borer
4. nodule spittlebug
5. alfalfa root knot nematode

1. Which of the following would be your least preferred companion crop for spring establishment of forages?

1. winter rye
2. flax
3. spring oats
4. spring barley
5. spring wheat

1. This disease prevents fall seeding of forage legumes in Southern IN and OH.

1. bacterial wilt
2. rhizoctonia
3. fusarium
4. verticillium
5. sclerotinia

1. Which one of the following is NOT a term used to describe soil structure?

1. prismatic
2. blocky
3. sandy
4. platy
5. columnar

1. Red clover-alfalfa mixtures are rarely recommended because

1. common insect pests problems
2. common disease pest problems
3. maturity differences
4. seedling vigor differences
5. a and b

1. If you are growing alfalfa at a site in the Southern Hemisphere where the killing frost in autumn occurs May 1, your last cutting should be taken no later than

1. September 15
2. December 1
3. January 15
4. March 15
5. April 15

1. The nutrient that stimulates seedling root growth and is often key for successful establishment is

1. Ca
2. Pb
3. Mg
4. P

Add a line to the graph below showing how yield of protein (T/A) changes with increasing values of MSC. Using all the information on the graph, including the line you have added, what is the best MSC to harvest this alfalfa? Explain.

If you seed alfalfa at 18 pounds per acre using lime-coated seed, what is the actual amount of seed you are sowing per acre? How much lime are you applying per acre? Is this amount of lime likely to alter pH of the soil? Explain. A second lot of uncoated seed you purchase contains 3% seed of other species, 2% inert matter, and the alfalfa has an 85% germination rate. To seed 18 pounds per acre of pure, live alfalfa seed (PLS) you need to sow how many pounds of seed per acre? Show your work.

On the axis below I have drawn a line showing how forage intake changes with increasing IVDMD. At low IVDMD values there is a close association between IVDMD and intake. Why? At high IVDMD values intake of the forage no longer increases. Explain? Name two things you could do to improve IVDMD of a pasture.