In liberal quantities, as it is likely to be where no leaching

has occurred. The deep-feeding roots can then supply

food and moisture abundantly.. The right kind of bacteria

must also be present, since in their absence the young

plants grow only a few inches high and then die. Some

soil from an old field scattered over the new patch in-

oculates it if the necessary bacteria are lacking in the

new seed-bed. Porous sub-soils are desirable for root

expansion ; the plants tolerate some gravel.

Water-logging seriously hinders development of the

plant by preventing aeration and by causing alkali

accumulation at the surface. Young plants suffer quickly

from salt concentrations ; but when older, a corky crown

enables the plant to resist girdling. Adaptability of the

crop to either extensive or intensive culture strengthens

its position as one of the principal crops in the West.

Alfalfa responds readily to manuring, irrigation, and

cultivation by increased returns; it also produces much

forage on dry-farms. Then, too, it yields best when

grown only five or six years on one piece of ground, but

Alfalfa 263

will continue to produce hay for ten, fifteen, or even

twenty years when conditions are favorable. That such

a crop is widespread is natural, particularly since it is

most palatable and nutritious.

282. Preparation of the land and seeding. — Fall-

plowing fines the seed-bed and allows rainfall to enter

the soil freely ; both of these are important for planting.

Small seed cannot get a hold unless food and moisture

are at hand. Liberal applications of well-rotted farmyard

manure warm the soil and increase the available water

and plant-food. After such preparation, spring-planting

should give good stands. If deep cultivation is practiced

the roots penetrate more easily. Lime is necessary on

acid soils.

Since fall-planting gives as good results as spring-

planting, farmers often plant then to save time in the

spring and to get a larger harvest next season. In this

case, the previous crop must come off the land generally

by August in order to make possible the ready prepara-

tion of a fine, moist, porous, yet firm seed-bed. August

or even July seeding permits the plants to establish them-

selves before winter sets in. When spring planted,

alfalfa should begin growth as soon as the land is warm.

One to five pounds of seed to an acre have given full

stands, though from ten to twenty are more satisfactory.

From twenty to thirty pounds are required for successful

stands in humid regions or on soils in poor condition.

Drills are almost universally used. Nurse crops of

barley, oats, or wheat may, or may not, be desirable.

They are necessary only on very hard or very loose soils.

In Algeria row cultivation pays, but in American hayfields

it is not used, except in small plats planted for seed.

283. Treatment during growth. — Some farmers har-

row with spike-tooth, spring-tooth, or disk harrows in

264 The Principles of Agronomy

spring or fall. Insects, disease, or weeds may necessitate

special attention. Light applications of farm manure

pay on some, and irrigation on all soils in arid sections.

Irrigation water up to about forty inches brings in-

creased returns. From one to ten applications are made

either by flooding or in shallow furrows which aid in leading

the water over difficult patches or in covering large areas

with small streams. Over-irrigation menaces some dis-

tricts, since flooding for more than one day at a time may

" drown *' the plants and permit frost to do considerable

injury. Fall, early spring, and winter irrigation are all

important in regions of scarce water and mild winters.

Conservation of rainfall is a fundamental economy in

all dry regions.

284. Harvesting. — Under normal conditions, the best

time to cut the crop for hay is in early bloom. Rakes

may follow the mower almost immediately — directly on

dry-farms and well-drained land. Irrigated alfalfa cures

best if piled in small cocks within a few hours of cut-

ting — the same day if possible. In this way farmers

can save the leaves on the stems, which makes the hay

more valuable than swath-cured hay. In rainy weather,

moreover, hay suffers more in the swath than in com-

pact piles.

When bull-rakes are u^, hay cures in heavy windrows

and is pushed to the stack without being loaded on wagons.

Various kinds of forks and nets and several types of der-

ricks unload the wagons, which are loaded by hand almost

entirely, though loaders are used in some sections. On

dry-farms, a ton to the acre pays; one and one-half to

two and one-half tons are frequent. Four or five tons

for the season is a good return under irrigation, though

six to eight are harvested from an acre under favorable

conditions.

Alfalfa

- Most hay is kept out-of-doors.

Stacks with upright sides with middles high and built

solid from the ground up, topped with rounding slopes

Fm. 71. —A

device fur Btackini

that leave no " shoulders " for storms to enter keep well,

while irregular squatty piles lose heavily. Good stacking

266 The Princi'ples of Agronomy

requires much akill. Sheds sre preferable, since it is

not necessary to stack carefully under cover.

Most hay is fed on the farm or marketed loose in the

vicinity. When shipments are made, the hay is com-

pressed into bales weighing from 50 to 150 pounds. Baled

and loose hay are usually weighed on wagons for market,

although stacks are often measured. Inaccuracy in

Fig. 72. — Hay should be fed on the farm.

measuring due to variation in shape, regularity, and

density cause this to be unsatisfactory in many instances.

286. Use and value. — In palatability, digestibility,

nutrition, and healthful ness, alfalfa hay leads. Some

horsemen prefer timothy because alfalfa Is laxative for

driving horses. A part of the preference for timothy is,

however, due to custom. Work animals need only moder-

ate grain ration when alfalfa Is fed because of the high

protein content. It excels as roughage for dairy cows.

Alfalfa 267

beef cattle, and sheep. As silage it has not been success-

ful because of difficulty in compacting.

Ground hay is used in mixed feeds as alfalfa meal.

It wastes less and compounds in rations more readily,

but otherwise it has no advantage over hay.

Alfalfa pasturing is widely practiced in spite of the

danger of bloat to cattle and sheep. Dew-covered leaves

eaten by hungry stock may prove injurious. Horses

and hogs may feed on alfalfa pastures any time; If

cattle are left continuously on the feed night and day,

danger diminishes but it never disappears. Wisdom is

necessary in pasturing cattle and sheep on the growing

crop. After haying, nearly all .fields are grazed over

mdiscriminately. Withered stands need cause no alarm.

Extremely close pasturing weakens the alfalfa, for it is

not stoloniferous and forms no true sod.

287. Mixtures are generally detrimental ii\ that they

lessen the yield. On account of maturing at a different

time, they also hurt the quality of the hay by introducing

coarse, woody stems or undesirable beards. Orchard-

grass, timothy, Kentucky blue-grass, and Bermuda-

grass are mixed with alfalfa purposely or creep in nat-

urally, but they are unsatisfactory and are considered

weeds. Squirrel-tail, locally known as foxtail (Hordeum

jvbatum), dodder, sweet clover, yellow trefoil, June-grass

quack-grass, and crab-grass all cause trouble. Thorough

harrowing and occasional plowing are the remedies for

almost all weeds in alfalfa.*

288. Enemies. -^ Besides weeds, root-rot, stem-blight,

leaf-spot, and several minor diseases do varying damage

to the crop. Rotation and cultivation largely control

them. Stem-blight, which seriously attacks the stems

of the first crop only, can be controlled by cutting as

soon as the disease appears.

268 The Principles of Agronomy

No widespread insect does constant damage. Grass-

hoppers may be disregarded if fall-plowing and clean

farming are practiced. Hibernations are thus destroyed.

Fia. 73. — Dodder on alfalfa plants.

Swarms from waste lands occasionally cause trouble.

Various traps for catching them have been devised.

The chalcis fly has recently done much seed injury in

Alfalfa 269

the West. It enters the ovary at bloom, lives inside the

seed, and bores out by a small clear-cut hole in the pod

just before maturity. Thrips also injure the seed-crop

at blooming time.

In 1905, the alfalfa leaf-weevil (Phytonomus posticus)

appeared in Utah and has since spread rather widely

over the state and into southern Idaho and south-

western Wyoming. Small green larvae feed on the

growing buds, usually of the first crop, thus delaying

the second crop and causing the third cutting to be

small or lacking. If the first crop is cut as soon as

the larvse appear in numbers sufficient to do marked

injury, and if the land is thoroughly spring-toothed

followed by a weighted brush-drag after the surface

has dried, the weevil nearly disappears on that patch

for the rest of the season. Besides the good which

cultivation does in destroying weeds and insects, it con-

serves moisture by forming a mulch. Contrary to public

opinion, the seed cannot carry the insect into new dis-

tricts.

289. Seed production is confined almost entirely to

dry regions because constant moisture encourages the

growth of new shoots which lessen seed bearing. Half

the seed produced is on irrigated lands where water can

be withheld. Dry-fanns produce most of the rest.

Second-crop alfalfa bears most of the seed. Even in

arid regions, seed-producing sections are isolated valleys

or areas. Row cultivation has given the best yields of

seed on some arid farms.

Seed alfalfa generally ought to be thinly sown.

Bumble bees aid in cross pollination but much self-

fertilization takes place.

Mowers or binders cut the seed stand and threshers

are used to separate the straw from the seed. The straw