msu-ceco/aec_v1 · Datasets at Hugging Face

text stringlengths 0 1.09k
Successful organic systems generally rely on multiyear, soil fertility and pest management plans.
Crop rotations that minimize bridging of diseases and insects from one year to the next also help the main crop remain healthy and better able to withstand other abiotic and biotic stresses.
The management plan may include cover crops and the use of crop seed free of disease and weed seed.
Critical criteria for getting a "good" start include seedbed preparation, optimal planting dates and seeding rates, and the use of approved materials.
Alfalfa can be grown for 2 to 3 years to help minimize weeds.
When planting alfalfa, choose a variety that regrows quickly and use a companion crop such as oats to help control weeds during alfalfa establishment.
In trials at South Dakota State University, it has been found that no herbicides are needed during establishment, and even though the field may be quite weedy, alfalfa can establish well.
Cut alfalfa at optimum times and heights, leaving enough plant to provide vigorous regrowth, and do not cut too late in the fall , SO that root carbohydrates have sufficient time to replenish for overwintering conditions.
In the first year, if planted with oats, cut oats at heading , and then allow the alfalfa to grow until midto late-bloom.
This typically is the only cut during the first year.
In the second and third years, alfalfa should be cut two or three times at recommended timings.
A benefit to alfalfa in the rotation is that weeds are also cut and not allowed to go to seed.
Typically, this will help deplete the weed seed bank and the fast regrowth of alfalfa will not allow new weeds to establish.
Do not allow the stand to stay in SO long that it becomes weak and noncompetitive.
Another concern if the stand stays in too long is that alfalfa will dry the soil.
These concerns must be balanced against the value of a good alfalfa crop and the weed control that it brings to the system.
When coming out of alfalfa, tillage should be done in the fall or spring, preceding corn planting.
The mechanical disruption of the terminated alfalfa will slow its regrowth, and volunteer alfalfa plants, even if present, typically do not result in reduction of corn yields.
Smother crops can provide an environment where weeds do not thrive and weed seed banks can be depleted.
Buckwheat, cereal rye, sorghum, corn for silage, and other crops may be used for this purpose.
Typically, seeding rates are high and rows are narrow to get early canopy cover.
If planted in narrow rows, cultivation is not used for in-season control, whereas wide-row plantings may require between-row weed control to minimize weed populations.
Short-season spring crops may be followed with overwintering crops.
Residues may be left on the field to further hamper weed establishment.
Cover crops planted after a short-season spring crop or interseeded into crops after the critical weed-free period can also provide some weed suppression.
Vigorous cover crops not killed by overwinter conditions must be controlled through physical means prior to seeding cash crops because these vigorous plants will act as weeds.
Flail mowing before seed set in cereal rye has provided successful control in the spring, as has roller-crimping immediately after rye flowering.
The mowed or crimped rye can form mulch and, if thick enough , prevents emergence of weed seedlings.
Additionally, some cover-crop species, including rye and radish , have allelochemicals in the residue that are leached into the soil, further hampering weed-seed germination and reducing weed pressure.
Physical Weed Control for Weed Management
Physical weed control is the most widely used method for immediate weed control in organic systems.
Plastic barriers and hand-hoeing may be used throughout the field to minimize weeds in high-value crops, such as sweet corn, and transplanted crops, such as tomatoes and peppers.
In grain and commodity crops, these operations may be too expensive, except in small areas where extra weed management may be needed, such as isolated patches of perennial weeds.
Other physical means of weed control include cultivation , flaming, hoeing, and abrasive-grit applications.
Many types of cultivation implements are available and may be used once or many times during the season.
Cultivation provides a clean seedbed and can be used to provide immediate control of weeds between the rows.
In the Midwest, two or three cultivations are typical for organic corn grain systems.
Timing for all cultivation operations is critical, and it may take several years to establish optimal timing for weed control in your fields.
However, complacency and performing the same operation at the same time every year will result in a spread of species other than those that were originally problematic.
Rotary hoeing and harrowing can be used if the corn and weeds are not too large.
Rotary hoeing on a diagonal, rather than up and down the rows, at 10 to 12 mph is purported to provide the greatest weed control.
Figure 44.2 Rotary hoe operation to remove small weeds.
There are challenges with cultivation that should be considered prior to adoption.
In rolling landscapes, erosion possibilities may outweigh the benefits of tillage and should be assessed because permanent damage can occur to soils with one untimely operation.
Soil health may also be reduced by untimely operations causing crusting, reduced water infiltration, and reduced organic matter and residues in surface soils.
Mulching with residues, plastic, or approved organic plant meals hampers weed germination, establishment, and development.
Meal application rates are often very high, at hundreds of pounds per acre.
Placement should be between rows SO that crop growth and development are unimpeded.
However, within-row weed management should not be forgotten, as weeds
closest to the crop tend to cause the greatest yield loss.
If within-row weeds become a problem, abrasive grits sprayed toward the base of the crop plants, hand-hoeing, or shielded cultivators to get as close to the crop as possible may need to be used.
Hand-hoeing is a time-tested approach to control weeds.
However, the practice is often overlooked in organic production fields because of cost and labor requirements.
Notwithstanding, new infestations of a weed, control of within-row weeds, or control of scattered plants may warrant individual attention.
Weed seeds can last in the seed bank for 3 to 50 years, and one weed can produce several hundred to several hundred thousand seeds.
"An ounce of prevention, can be worth pounds of cure" through careful management, weeds can be controlled.
Flaming, Steaming, and Microwave Systems
Flaming, steaming, and microwave systems have been used to kill weeds through desiccation and hightemperature exposure.
Young weeds can be killed quite readily with these practices.
Larger weeds need to be treated for a longer period of time and the growing point must be affected.
The problem with these methods is that the contact time needs to be optimized, often leading to slow operating speeds for equipment, low labor efficiency, and high fuel bills.
Caution must be Figure 44.4 An image of a propane flamer.
Typically, corn can withstand the heat if the growing point is below the soil surface, but care must be taken not to directly heat the crop, once the growing point is above ground.
Figure 44.3 Carefully tended cropping areas in Vietnam display minimal weed problems.
Abrasive-grit systems are being tested by SDSU, the University of Illinois, and USDA-ARS for their ability to control weeds.
The machine uses organically certified grits applied at 100 psi to in-row weeds with nozzles pointed toward the base of the plant.
The grit blasts the weeds causing enough damage to kill young broadleaf weeds and injure the growing points of older weeds.
We found that two operations, one at V1 or V2 and another at V3 or V4, controlled broadleaf Figure 44.5 Four-row grit applicator for weed control weeds and maintained cash-crop yield.
If the operation in row crops designed by SDSU Ag & Biosystems occurred at V5, weeds were well-developed and, while Engineering Dept.
Ground corncob grit was used as the spray.
earlier interference, corn yield was reduced unpublished data).
Timing on grass weeds needs more research because of the ability of a defoliated plant to regrow if the growing point is below ground at the time of treatment.
Optimization of grit types, rates, timing, and spectrum of weeds controlled are still in the early stage of research.
Robotic Hoeing and Flaming
Recent developments in nonchemical weed control include the "Robovator," a robotic implement that hoes weeds within crop rows.
In this case, the crops have to be precision-planted and the Robovator uses a knife to remove any and all plants between the spaced crop plants.
An equally innovative implement is a robotic flame weeder that senses the presence of a crop plant and withholds a flame jet, but singes all other plants.
There are some chemical herbicides approved for use in organic production, however, the efficacy of these applications are inconsistent in South Dakota.
In 2015, sprays approved for application for weed control in organic systems with or without approved organic surfactants included: clove, cinnamon, and garlic oils; citric acid; and ammonium nonanoate.
Reports from credible research trials should be consulted prior to purchase, as rates, surfactant types, and timing of applications have had mixed results.
As with any pesticide application, always read and follow label directions.
Premium prices for organically grown crops can be financially beneficial.
However, based on numerous Camera detects crop plants surveys of organic producers, weed management is one of the most challenging aspects of growing organic crops.
As in conventional systems, there is no one "silver bullet" technique for weed control.
Understanding the biology of the weedy species infesting the area will help in planning timely operations to disrupt weed establishment and growth.
The use of many diverse techniques and crop rotations are key aspects to minimize weed problems in organic farming.
Figure 44.6 Robovator that was developed to combine "smart sensors" with knives to mechanically hoe organic fields.
Figure 44.7 A "smart" flame weeder that uses sensors to detect weeds in the interrow of transplanted crops.
Note that some areas are being flamed and other areas are not.
MAINTAINING DRIP IRRIGATION SYSTEMS
BY GARY A.
CLARK WILLIAM J.
LAMONT JR.
CHARLES W.
MARR DANNY ROGERS
Drip irrigation systems are becoming more widely used for horticultural crop production, especially vegetable crops.
The system must function efficiently during the entire growing season.
Failure at a critical point in the crop production cycle can cause loss of the entire crop.
System failures often are due to inadequate maintenance of the system, especially if fertigation is being utilized to supply nutrients to the plant's root zone.
Maintenance of the drip irrigation system does take time and understanding; however, maintenance is critical for its successful use.

Successful organic systems generally rely on multiyear, soil fertility and pest management plans.

Crop rotations that minimize bridging of diseases and insects from one year to the next also help the main crop remain healthy and better able to withstand other abiotic and biotic stresses.

The management plan may include cover crops and the use of crop seed free of disease and weed seed.

Critical criteria for getting a "good" start include seedbed preparation, optimal planting dates and seeding rates, and the use of approved materials.

Alfalfa can be grown for 2 to 3 years to help minimize weeds.

When planting alfalfa, choose a variety that regrows quickly and use a companion crop such as oats to help control weeds during alfalfa establishment.

In trials at South Dakota State University, it has been found that no herbicides are needed during establishment, and even though the field may be quite weedy, alfalfa can establish well.

Cut alfalfa at optimum times and heights, leaving enough plant to provide vigorous regrowth, and do not cut too late in the fall , SO that root carbohydrates have sufficient time to replenish for overwintering conditions.

In the first year, if planted with oats, cut oats at heading , and then allow the alfalfa to grow until midto late-bloom.

This typically is the only cut during the first year.

In the second and third years, alfalfa should be cut two or three times at recommended timings.

A benefit to alfalfa in the rotation is that weeds are also cut and not allowed to go to seed.

Typically, this will help deplete the weed seed bank and the fast regrowth of alfalfa will not allow new weeds to establish.

Do not allow the stand to stay in SO long that it becomes weak and noncompetitive.

Another concern if the stand stays in too long is that alfalfa will dry the soil.

These concerns must be balanced against the value of a good alfalfa crop and the weed control that it brings to the system.

When coming out of alfalfa, tillage should be done in the fall or spring, preceding corn planting.

The mechanical disruption of the terminated alfalfa will slow its regrowth, and volunteer alfalfa plants, even if present, typically do not result in reduction of corn yields.

Smother crops can provide an environment where weeds do not thrive and weed seed banks can be depleted.

Buckwheat, cereal rye, sorghum, corn for silage, and other crops may be used for this purpose.

Typically, seeding rates are high and rows are narrow to get early canopy cover.

If planted in narrow rows, cultivation is not used for in-season control, whereas wide-row plantings may require between-row weed control to minimize weed populations.

Short-season spring crops may be followed with overwintering crops.

Residues may be left on the field to further hamper weed establishment.

Cover crops planted after a short-season spring crop or interseeded into crops after the critical weed-free period can also provide some weed suppression.

Vigorous cover crops not killed by overwinter conditions must be controlled through physical means prior to seeding cash crops because these vigorous plants will act as weeds.

Flail mowing before seed set in cereal rye has provided successful control in the spring, as has roller-crimping immediately after rye flowering.

The mowed or crimped rye can form mulch and, if thick enough , prevents emergence of weed seedlings.

Additionally, some cover-crop species, including rye and radish , have allelochemicals in the residue that are leached into the soil, further hampering weed-seed germination and reducing weed pressure.

Physical Weed Control for Weed Management

Physical weed control is the most widely used method for immediate weed control in organic systems.

Plastic barriers and hand-hoeing may be used throughout the field to minimize weeds in high-value crops, such as sweet corn, and transplanted crops, such as tomatoes and peppers.

In grain and commodity crops, these operations may be too expensive, except in small areas where extra weed management may be needed, such as isolated patches of perennial weeds.

Other physical means of weed control include cultivation , flaming, hoeing, and abrasive-grit applications.

Many types of cultivation implements are available and may be used once or many times during the season.

Cultivation provides a clean seedbed and can be used to provide immediate control of weeds between the rows.

In the Midwest, two or three cultivations are typical for organic corn grain systems.

Timing for all cultivation operations is critical, and it may take several years to establish optimal timing for weed control in your fields.

However, complacency and performing the same operation at the same time every year will result in a spread of species other than those that were originally problematic.

Rotary hoeing and harrowing can be used if the corn and weeds are not too large.

Rotary hoeing on a diagonal, rather than up and down the rows, at 10 to 12 mph is purported to provide the greatest weed control.

Figure 44.2 Rotary hoe operation to remove small weeds.

There are challenges with cultivation that should be considered prior to adoption.

In rolling landscapes, erosion possibilities may outweigh the benefits of tillage and should be assessed because permanent damage can occur to soils with one untimely operation.

Soil health may also be reduced by untimely operations causing crusting, reduced water infiltration, and reduced organic matter and residues in surface soils.

Mulching with residues, plastic, or approved organic plant meals hampers weed germination, establishment, and development.

Meal application rates are often very high, at hundreds of pounds per acre.

Placement should be between rows SO that crop growth and development are unimpeded.

However, within-row weed management should not be forgotten, as weeds

closest to the crop tend to cause the greatest yield loss.

If within-row weeds become a problem, abrasive grits sprayed toward the base of the crop plants, hand-hoeing, or shielded cultivators to get as close to the crop as possible may need to be used.

Hand-hoeing is a time-tested approach to control weeds.

However, the practice is often overlooked in organic production fields because of cost and labor requirements.

Notwithstanding, new infestations of a weed, control of within-row weeds, or control of scattered plants may warrant individual attention.

Weed seeds can last in the seed bank for 3 to 50 years, and one weed can produce several hundred to several hundred thousand seeds.

"An ounce of prevention, can be worth pounds of cure" through careful management, weeds can be controlled.

Flaming, Steaming, and Microwave Systems

Flaming, steaming, and microwave systems have been used to kill weeds through desiccation and hightemperature exposure.

Young weeds can be killed quite readily with these practices.

Larger weeds need to be treated for a longer period of time and the growing point must be affected.

The problem with these methods is that the contact time needs to be optimized, often leading to slow operating speeds for equipment, low labor efficiency, and high fuel bills.

Caution must be Figure 44.4 An image of a propane flamer.

Typically, corn can withstand the heat if the growing point is below the soil surface, but care must be taken not to directly heat the crop, once the growing point is above ground.

Figure 44.3 Carefully tended cropping areas in Vietnam display minimal weed problems.

Abrasive-grit systems are being tested by SDSU, the University of Illinois, and USDA-ARS for their ability to control weeds.

The machine uses organically certified grits applied at 100 psi to in-row weeds with nozzles pointed toward the base of the plant.

The grit blasts the weeds causing enough damage to kill young broadleaf weeds and injure the growing points of older weeds.

We found that two operations, one at V1 or V2 and another at V3 or V4, controlled broadleaf Figure 44.5 Four-row grit applicator for weed control weeds and maintained cash-crop yield.

If the operation in row crops designed by SDSU Ag & Biosystems occurred at V5, weeds were well-developed and, while Engineering Dept.

Ground corncob grit was used as the spray.

earlier interference, corn yield was reduced unpublished data).

Timing on grass weeds needs more research because of the ability of a defoliated plant to regrow if the growing point is below ground at the time of treatment.

Optimization of grit types, rates, timing, and spectrum of weeds controlled are still in the early stage of research.

Robotic Hoeing and Flaming

Recent developments in nonchemical weed control include the "Robovator," a robotic implement that hoes weeds within crop rows.

In this case, the crops have to be precision-planted and the Robovator uses a knife to remove any and all plants between the spaced crop plants.

An equally innovative implement is a robotic flame weeder that senses the presence of a crop plant and withholds a flame jet, but singes all other plants.

There are some chemical herbicides approved for use in organic production, however, the efficacy of these applications are inconsistent in South Dakota.

In 2015, sprays approved for application for weed control in organic systems with or without approved organic surfactants included: clove, cinnamon, and garlic oils; citric acid; and ammonium nonanoate.

Reports from credible research trials should be consulted prior to purchase, as rates, surfactant types, and timing of applications have had mixed results.

As with any pesticide application, always read and follow label directions.

Premium prices for organically grown crops can be financially beneficial.

However, based on numerous Camera detects crop plants surveys of organic producers, weed management is one of the most challenging aspects of growing organic crops.

As in conventional systems, there is no one "silver bullet" technique for weed control.

Understanding the biology of the weedy species infesting the area will help in planning timely operations to disrupt weed establishment and growth.

The use of many diverse techniques and crop rotations are key aspects to minimize weed problems in organic farming.

Figure 44.6 Robovator that was developed to combine "smart sensors" with knives to mechanically hoe organic fields.

Figure 44.7 A "smart" flame weeder that uses sensors to detect weeds in the interrow of transplanted crops.

Note that some areas are being flamed and other areas are not.

MAINTAINING DRIP IRRIGATION SYSTEMS

BY GARY A.

CLARK WILLIAM J.

LAMONT JR.

CHARLES W.

MARR DANNY ROGERS

Drip irrigation systems are becoming more widely used for horticultural crop production, especially vegetable crops.

The system must function efficiently during the entire growing season.

Failure at a critical point in the crop production cycle can cause loss of the entire crop.

System failures often are due to inadequate maintenance of the system, especially if fertigation is being utilized to supply nutrients to the plant's root zone.

Maintenance of the drip irrigation system does take time and understanding; however, maintenance is critical for its successful use.