NDSU Crop and Pest Report

Plant Science


ISSUE 10   July 8, 2004

DRY BEANS: GROWTH AND MATURITY

Two basic plant types are found in dry edible bean, determinate (bush) or indeterminate (vining or trailing). Cultivars may be classified according to plant types. For example, navy beans may be either of the bush or vining types. In the determinate type, stem elongation ceases when the terminal flower racemes of the main stem or lateral branches have developed. On indeterminate types, flowering and pod filling will continue simultaneously or alternately as long as temperature and moisture permits growth to occur. Most of our pinto varieties are indeterminate.

The question of dry edible bean maturity has been debated for many years. Compared to many other plants, the dry edible bean is orderly in its growth and development. There are two basic stages of growth: The vegetative and the reproductive. Growth at any point in the vegetative stage can be determined and defined by counting the number of nodes on the main stem. The reproductive stage begins when the first flower opens and is described and characterized by observing pod development and seed fill within the developed pod. Both vegetative and reproductive stages can further be separated into two periods for a total of four major growth periods in the life of a bean plant. They are:

Germination and stand establishment (V1 to V2)

Rapid vegetative growth (V3 to V8)

Flowering and pod development (R1 to R4)

Pod fill and maturation (R5 to R9)

The time required for the two growth periods of germination and stand establishment and flowering and pod development under the same growing conditions is the same for all varieties. Differences in maturity of varieties are experienced during the two periods of rapid vegetative growth and pod fill and maturation. The way it works is that late maturing varieties will require a longer period of time to pass through the rapid vegetative growth period than will early maturing varieties. This increase in time results in increased vegetative growth, capable of producing and filling pods over an extended period of time.

This sounds simple and straight forward and leads one to wonder why two people can come up with a different maturity value for the same bean variety. The reason seems to be that maturity for a given variety may be extended during one or more of the growth periods.

The developing bean will respond to many factors including planting in cool and/or wet soils, planting in dry soils, insufficient soil moisture, excessive soil moisture, high temperatures during flowering which delays pod set, or low temperatures during maturation. Maturity of a variety may also be extended by preplant herbicide injury, excess of or lack of certain plant nutrients, low plant stands, beans following alfalfa in a rotation, or damage from hail. Some of these factors can be controlled, others cannot. It's important to consider these factors, however, when comparing differing maturity dates for a bean variety. One of the above factors will usually be responsible for the difference.

 

FOXTAIL MILLETS FOR HAY

Foxtail millets are grown primarily for short season emergency hay crops. Several landraces have been developed over time and are grown in North Dakota.

Planting of foxtail millets can be delayed until mid-June into early July. When used for emergency hay production, late planting is usually encountered.

Plant into moist soil about 1 inch deep. Shallower seeding may be desirable on heavy textured soils with good moisture. Germination is fairly rapid but early seedling vigor is lacking.

Foxtail millets have low seedling vigor and in general are poor competitors with weeds. A seeding rate of 15 to 30 pounds per acre is recommended. The higher rates are recommended in eastern North Dakota with the higher rainfall potential. In western North Dakota, 15 pounds is adequate on weed free fields.

Hay Millets Include The Following:

Common Foxtail millet is fine-stemmed and leafy. Seed head is cylindrical and compact and tapers toward the tip. The lower portion is less compact than the mid- and tip portions. Seed head varies from 5/8 to 3/4 inch in diameter and 4 to 6 inches in length with pale yellow bristles. It is one of the earliest foxtail millets, maturing in about 70 days and producing a hay crop in about 50 days.

Siberian millet has medium-sized stems and possesses some drought tolerance. The seed head is cylindrical, 5/8 to 3/4 inch in diameter, 4 to 6 inches long, and has purple bristles. It matures in about 75 to 80 days and produces a hay crop in 55 to 60 days. Manta, a South Dakota release, is an early Siberian millet.

Hungarian millet is characterized by a small, compact, slightly lobed seed head which is 1/2 to 5/8 inch in diameter and 4 to 6 inches long. Bristles vary in color from clear to pale yellow through purple and black. Stems are medium in size. It is reported to do better under more favorable moisture conditions. Maturity is about 70 days and a hay crop can be ready in about 55 days.

German millet has thicker stems and broader leaves. The seed head is distinctly lobed, measuring 1 to 1 inches in diameter and 6 to 9 inches long. Bristles are greenish to purple. It is a longer season foxtail, which takes about 90 or more days to mature and 65 to 70 days to produce a hay crop. Because of its increased stem size, it takes better management than the other foxtail millets to produce good quality hay.

Harvest hay millets in the late boot to early bloom growth stage. Any delay after full head emergence will reduce quality. Bristles become hard as maturity approaches and may cause sore mouth, lump jaw and eye infections when fed to livestock. Hay protein content is highest when the ratio of leaves to stems is high. Curing foxtail millet requires attention as light stands tend to sun dry rapidly after cutting, while heavy stands, especially of the German type, cure at a slower rate. If expected yield levels are greater than 1 tons per acre, crimping will help the curing process. Potential yield of foxtail millet hay is influenced by moisture relationships. Research trial yields from NDSU Research/Extension Centers have ranged from 1.5 to 3.4 tons/acre.

Dr. Duane R. Berglund
NDSU - Extension Agronomist
dberglun@ndsuext.nodak.edu  

 

MANAGEMENT PRACTICES TO AID IN HARVESTING SMALL GRAINS

It is time to start thinking about harvesting small grains, at least the winter wheat crop. There are basically two management practices that are used to aid in harvesting small grains, swathing/windrowing and the pre-harvest application of herbicides. For fields with green weeds and late emerging tillers, traditionally small grains were swathed in order to speed up the drying process. Now there are a number of herbicides labeled for pre-harvest use in small grains (except oats) for weed control and as harvest aids (see the 2004 North Dakota Weed Control Guide for a complete listing). Of the herbicides registered for pre-harvest application most target weeds that were not adequately controlled earlier in the growing season and that are green and a nuisance during the harvesting operation. Weeds, however, prior to small grain harvest are generally tall and difficult to control with herbicides and can take a week or more to dry down even with an effective treatment. Herbicide applications at this stage will not increase crop yield, but may help reduce weed seed production.

Glyphosate, in addition to controlling weeds, is labeled for use in aiding the dry down of the crop itself (as opposed to controlling and drying down weeds in the crop). Glyphosate is a systemic herbicide and takes from 7 to 10 days to effectively kill the growing parts of the crop so the dry down process is not immediately visible.

Direct combining, swathing or pre-harvest glyphosate compared

The advantages of swathing over direct combining are:

  • Faster and more even dry down if significant amounts of green weeds or late emerging green tillers in the crop are present;
  • Less hail damage of spikes in the swath should a hail storm strike before combining.
  • The disadvantages of swathing are:

  • An additional pass through the field is required;
  • Significant kernel bleaching, pre-harvest sprouting and increased disease development on the kernels if swaths are subject to heavy rains or persistent dews.
  • The advantages of applying glyphosate pre-harvest are:

  • Controls some weeds in addition to hastening crop dry down;
  • May enable more uniform drying than an untreated direct combined field;
  • The standing crop has faster dry down after a rain than a swathed field.
  • The disadvantages of applying glyphosate pre-harvest:

  • Requires an extra trip across the field;
  • Potential for damage to nearby crops due to spray drift;
  • Germination of the crop to be harvested can be adversely affected if applied too early.
  • Swathing and glyphosate should only be applied after the crop has reached physiological maturity. Physiological maturity occurs at a grain moisture content of about 30%. At this moisture content the grain is in the hard dough stage and if you run your thumb nail across the kernel, the indentation will remain. Applying glyphosate before physiological maturity will reduce the yield and test weight of the crop and will almost certainly reduce its germination potential.

    Additional information on applying glyphosate pre-harvest:

  • Because of the potential to reduce germination if applied too early, glyphosate should not be used in fields that will be used for seed. Additionally, it is not to be used on barley intended for malt.
  • The label requires that pre-harvest applications of glyphosate must be made at least 7 days before harvest.
  • For rates and other information, refer to the label and the 2003 North Dakota Weed Control Guide.
  • Joel Ransom
    Extension Agronomist - Cereal Crops
    joel.ransom@ndsu.nodak.edu


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