(TRUE or FALSE) Forage quality of alfalfa increased with increasing stem density since the stems were finer.

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1 PLSC 320, Quiz II Name Lab section/time If you don't understand the question, mark it on the exam so that I can consider when I am grading this exam. Take all questions at face value, don't read additional meaning into them, especially the true or false questions. Pts 2 1. (TRUE or FALSE) Bromegrass and crested wheatgrass transplanted at 1 plant/ft2 or seeded at 5 seeds/ft2 produced less forage yield than higher plant or seed densities in the second year of production. (TRUE or FALSE) Forage quality of alfalfa increased with increasing stem density since the stems were finer. (TRUE or FALSE) Excellent stands of alfalfa can be established under a warm-season species like sudangrass seeded in 6-inch rows as long as the sudangrass is harvested timely. (TRUE or FALSE) The target species in weed control programs in establishing alfalfa should be the grass species because many broadleaf weeds have as good or better forage quality than alfalfa in early growth stages. (TRUE or FALSE) It is important to increase the seeding rate of alfalfa to 10 to 12 lb/a when establishing alfalfa with a companion crop since the companion crop is competing with the alfalfa and can reduce the establishment rate. (TRUE or FALSE) Dormant seeding of alfalfa is an excellent method to establish alfalfa whereas dormant seeding of grasses is discouraged due to potential winter kill of the seedlings. (TRUE or FALSE) Dr. Dave Franzen, extension soil specialist, has recently found that even here in North Dakota where soils are considered high in soil ph that liming of some soil areas may be necessary for maximum production of alfalfa. (TRUE or FALSE) Application of ammonium phosphate to alfalfa is never recommended because the legume plant can fix its own nitrogen.

2 (TRUE or FALSE) Wisconsin data shows that forage yield potential (increasing 0.2 tons/acre) and stand persistence (increasing from 3 to 4 years) are more important in the economic return on alfalfa acreage in a dairy operation than decreasing ADF and NDF by 2% each or increasing seed cost by $1/lb with a 15 lb/a seeding rate. (TRUE or FALSE) Most new cultivars of alfalfa today are highly resistant to the six diseases considered for multiple disease resistance. (TRUE or FALSE) Most alfalfa cultivars released are synthetic varieties Name three alfalfa insect pest commonly found in this area other than grasshoppers AND give the typical symptoms of the insect. potato leafhopper - v-shaped yellowing of tip of leaflet alfalfa weevil - skeletonized leaflets alfalfa blotch leafminer - white comma-shaped spot on leaflet 1 3. What is sod-seeding? introducing a species, usually a legume, into an untilled grass sod 3 4. Define contractile growth AND why is contractile growth important for the alfalfa plant? contractile growth is pulling below the soil surface the cotyledonary, unifoliolate, and possibly the first trifoliolate leaf nodes by C H O storage in the root. Contractile growth increases winterhardiness 3 5. How many plants/ft2 will give near maximum alfalfa yield during the first harvest year if uniformly distributed 5? Recommended seeding rate for alfalfa seeded without a companion crop is lb/a, but assuming a normal emergence rate of 67 %, a seeding rate of only 2 lb/a would give an adequate stand. 4.5 seeds/lb x The two most common alfalfa diseases found in North Dakota are common leafspot and Fusarium root rot ( some resistance exist for these diseases, but it is not complete) Why are companion crops used to establish alfalfa or grass forages? economic yield in first year, decreased weed competition, and erosion control.

3 4 8. Joe Concern call yesterday and was worried about his new alfalfa stand that he seeded on August 1. The plants were 8 to 10 inches tall and relatively uniformly distributed, but 35% of the area (mostly in windrow areas where volunteer grain occurred) had 1 to 2 plants/ft2, 40% of area had 5 to 6 plants/ft2, and 25% of the area had 20 plants/ft2. Joe wants to know whether to attempt to thicken up the stand next year. What would you recommend? kill volunteer grain Why? one plant/ft 2 = 80% of max rest had more than enough for maximum productivity, so don't overseed 4 9. Alfalfa varieties should be selected based on the following four characteristics forage yield>vernal, enhanced quality, stand persistance, and disease and insect tolerance The lower forage quality of a grass plant compared with alfalfa is due to this chemical component NDF that reduces intake Oat is the most competitive companion crop for both light and soil water; yet, it is the most common companion crop used. Why? used as forage and believe higher in quality What is "common" alfalfa seed? any alfalfa seed of unknown origin Seeding rate recommendations are based on (a. PLS, b. bulk seed) in grasses. Why? germination and purity lower in grasses than legumes The least competitive companion crop for both soil water.and light is (a. Barley, b. Wheat, c. Flax, d. Oat) Six diseases have been emphasized by alfalfa plant breeders and have been the primary distinguishing differences among most of the new varieties. These diseases are? Fusarium wilt Verticillium wilt Bacterial wilt Phytophthora root rot Anthracnose Aphanomyces A fully productive field of alfalfa will have at least this many stems/ft (give a 10 stem range) Why is the inoculation recommendations different in small-seeded (alfalfa) than large-seeded legumes? cheap insurance First, how do they differ? always recommended in small seeded, only when a similar legume hasn't been grown for 3+ years. Then answer the first part.

4 1 18. Why is a firm seedbed so important in establishing small-seeded legumes and grasses? for seed-soil moisture contact and seeding depth control With a quick look, this insect ( varigated cutworm ) causes areas of the field to appear as regrowth is lacking or very slow. On closer look, there are stems with the leaves totally removed, especially in the windrows following the first harvest Why are mid-september seedings of alfalfa generally not successful? alfalfa requires 6 to 8 weeks in order to reach perenniality List six advantages and four disadvantages of no-till or reducedtillage establishment of alfalfa. Advantages -great seed-soil moisture contact -less tillage cost -no special equipment -firm seedbed -less stand failures -less weed problems Disadvantages -herbicide-resistant weeds -trashy fields cause problems -weed control needed -wheel tracking in previous crop What is a crown AND how does the crown of an alfalfa plant differ from the crown of a wheat plant? Crown-lower stem composed of unelongated internodes and its associated buds. The crown of an alfalfa plant differs below ground vs. at soil surface for wheat. perennial vs. annual; rhizomes in alfalfa List four factors that affect the recommended seeding depth of a grass or legume (environmental factors excluded). 1. type of emergence 2. seed size 3. soil texture 4. soil compaction To enhance the forage quality of alfalfa, breeders must affect this physiological characteristic (not chemical characteristic) leaf to stem ratio Alfalfa has various root systems. This one characterizes alfalfa taproot. This one is concentrated in Spredor 3 creeping root. This one is used to increase heaving tolerance branched rooted. This one is rarely found rhizomatous.

5 1 26. The environment plays an important part in winter kill of alfalfa, but under the same environment and for the same variety, this factor is the most important aspect affecting the ability of a particular stand to survive a winter-injury year stand age What dormancy classes of alfalfa can we grow in this area (a. 1-2, b. 1-4, c d. 3-6, e. 7-9) Most grasses can overwinter adequately if they reach this leaf growth stage 1 to 2 leaf What dormancy level and stand persistence level would be ideal for an alfalfa cultivar for this environment? Dormancy Level = 4; Persistance Level 1 to Flemish alfalfas were the source of what desirable characteristic in alfalfa today? fast regrowth A pasture alfalfa like Alfagraze has been selected for persistence under grazing. What plant characteristics are associated with tolerance to grazing? 1. decumbent growth 2. slower regrowth 3. trampling tolerance Name five factors that affect the recommended planting rate. 1. soil water 2. soil fertility 3. seed quality 4. planting method 5. species 6. environment 7. companion crop 8. method of planting The alfalfa disease characterized by tap roots that have been cut off and generally is found on poorly drained soils with good rainfall is phytophthora root rot Alfalfa cultivars rated as highly resistant for a particular disease has (a. 25, b. 50, c. 75, d. >90) % of the plants resistant (TRUE or FALSE) The 2001 seeding rate results were significantly different from the 1970 seeding rate results indicating the need to keep the data current.

6 1 36. Two excellent sources of written information on alfalfa varieties are CASC and varietal trials of farm crops Why is it difficult for me to recommend a given alfalfa cultivar to a producer even though we presently are testing over 60 newly released cultivars (two reasons)? 1. strong mgt x cultivar interaction 2. releasing cultivars faster than we can test, moving on to new ones What is an annual alfalfa in this area AND give an example of an annual alfalfa variety. An annual alfalfa is a cultivar of alfalfa with little dormancy. An example is Nitro Name the two weeds that have developed resistance to the ALS class of herbicides and have become common problems in fields in eastern North Dakota Kochia and black nightshade. This species is also developing ALS resistance wild mustard The best weed control of annual grass and broadleaf weeds in seedling alfalfa can be obtained with this herbicide if ALS-resistant weeds are not present Pursuit. If using this herbicide, what adjuvant is recommended MSO and it should be applied at this growth stage 2 trifoliolates? If ALS-resistant weeds are present, then what is the best weed control program for clear-seeded alfalfa? Buctril and Poast or Select applied separately The best herbicide for broadleaf weed control in CRP seedings that used the wildlife mixture is buctril, but this component may be injured even under good environmental conditions sweetclover Many grass seeding rates are calculated by NRCS based on how many seeds/ft ? Upon my honor, I have neither given or received aid in writing this exam.