Late Summer Forage Seeding for Hay and Pastures

Aug 19, 2021

By Leanna Dupppstadt and Justin Brackenrich et.al

Late summer seeding of forages is generally the most successful in PA and allow for new or renovated stands to be well established by the following spring, boosting early yields. Spring seedings can be successful as well, but wet soil conditions, increased weed competition, and the possibility of summer droughts, can make it more difficult. Another advantage to fall seeding is having well-established stands in the spring which will be more competitive with weeds. Late summer is also the time when producers are less busy as compared to the hustle and bustle of spring.

For optimum forage crop establishment , forages should be planted at least 6 weeks before the first killing frost. This means that forage producers in Pennsylvania should seed cool-season perennials between mid-August to mid-September, depending on location. During this time, the weather is still warm enough to encourage establishment while beating the potential extreme temperatures that settle into our state by mid-fall. September rains encourage quick establishment and the warm days boost growth.

Typically, the ideal time to seed cool-season perennial forages across PA is:

August 10 – August 15 for Northern PA
August 15 – August 20 for Central PA
August 20 – September 10 for Southern PA

When renovating or establishing pastures or hay fields , producers need to pay close attention to two things, seeding depth and seed-to-soil contact. More failures in forage establishment occur because of improper seeding depth than any other cause. Forage seeds are very small and thus have a very small supply of stored energy to support the seedling until it emerges and can begin making its own energy. Seeds placed too deep are not likely to emerge.

Seeding Depth

Optimum seeding depth varies with soil type (sandy, clay, or loam), soil moisture, time of seeding and firmness of seedbed but generally is not more than 3/8 inch deep. A rule-of-thumb is that 5-10% of the forage seeds that are planted, should be on the soil surface after seeding. Ensuring that seeds are placed at the proper depth requires a firm seedbed. It is extremely difficult to accurately regulate seeding depth if the soil is soft and fluffy. On a properly firmed soil, an adult’s footprint should not be deeper than ½ inch, that is the rule-of-thumb regarding soil firmness. Forage seeds should be covered with enough soil to provide moist conditions for germination, but not so deep that the shoot cannot reach the surface.

Seed-to-Soil Contact

Proper seed-to-soil contact can be tricky when no-tilling into an established stand in an effort to restore or improve forage stands and special attention should be paid to seeding depth. Forage seeds need to absorb at least their own weight in water before germination begins. Unless the forage seed has been planted in saturated soils, the water generally moves into the seed from surrounding soil. Adequate seed-to-soil contact ensures maximum water movement into the seed in the shortest amount of time. Field situations that do not promote good seed-to-soil contact, such as cloddy or loose soil, generally results in extended germination periods and sporadic emergence. The use of press wheels on a grain drill or cultipacking after seeding can improve seed-to-soil contact.

If soil conditions are droughty and soil moisture is limited, then it would be best to delay planting. No-tilling maintains existing soil moisture whereas working the ground for summer seedings can greatly reduce soil moisture. If tilling, especially in a dry year, then seeding should be done earlier in the summer to conserve moisture.

Fall, or better called late-summer, forage seedings present the producer with the best opportunity for stand success as well as production success in the subsequent year. Typically fall seedlings will produce slightly less than a maintenance field, compared to a spring seeded forage which can produce as little as 30% of a maintenance forage field. Using this information for seeding dates, and field prep will help to ensure more success.

Source : psu.edu

Video: Turning Plant Defense Into a Management Strategy

Turning Plant Defense Into a Management Strategy

Understanding how a plant responds to stress is one thing.

Using that knowledge to make better management decisions is another.

Systemic acquired resistance, or SAR, is the plant's more direct defense response. When stress or infection occurs, the plant begins signaling throughout its system and preparing defensive compounds.

But if we know that response exists, can we help prepare the plant before the stress arrives?

The answer starts with understanding what triggers the response and what the plant needs to carry it out.

The Trigger and the Fuel

Salicylic acid plays an important role in triggering the SAR pathway.

Think of it as turning the truck on.

The engine may be running, but it still needs fuel to do the work.

In this case, manganese plays an important role in supporting the enzyme systems involved in the plant's defensive response.

This makes manganese status an important part of the conversation. Whether a producer is using tissue testing, sap analysis, or simply scouting for visible deficiency symptoms, the goal is to make sure the plant has adequate manganese available.

Manganese is required in relatively small amounts, but that does not make its role small.

If the plant receives a signal to defend itself but lacks the nutrition needed to support that response, it may struggle to carry out the process efficiently.

The trigger matters.

The fuel matters too.

Prepare Before the Stress Arrives

The best time to think about stress management is before the plant is overwhelmed.

Once a crop is already struggling, management can quickly turn into a game of catch-up.

This is similar to nitrogen management. Once a plant becomes severely deficient, correcting the problem does not necessarily erase the time and yield potential already lost.

Plant defense can work the same way.

Low-rate, targeted approaches designed to support the SAR pathway may fit best ahead of an expected stress event rather than after significant damage has already occurred.

That requires producers to think about predictable stress.

We may not know exactly what the weather will do tomorrow, but we generally know summer heat is coming. We know certain field conditions increase disease pressure. We know a herbicide application can temporarily stress a crop as the plant processes the chemistry.

Even a properly timed and labeled herbicide application can create a temporary response in the plant.

That does not mean the herbicide is bad.

Weeds can create significantly more yield loss than the temporary stress caused by controlling them.

The question is not whether we should eliminate every stressor.

The question is whether we can better prepare the plant to manage necessary and predictable stress.

Not All Stress Is Bad

Stress is a normal part of plant growth.

A perfectly stress-free environment does not exist in the field.

In fact, some stress is necessary for normal plant development. A plant responds to wind, temperature, moisture, sunlight, and countless other environmental signals throughout the season.

The environment is stress.

The plant's job is to manage it.

Problems begin when the stress load becomes greater than the plant's ability to respond.

Extreme heat, drought, high salt concentrations, disease pressure, and even certain management practices can add to that load.

This is where understanding SAR becomes useful.

Instead of waiting until the plant is visibly struggling, producers can begin identifying periods when stress is likely and make management decisions around those windows.

ISR Starts With the Soil

While SAR is a more direct defense response, induced systemic resistance, or ISR, brings the conversation back to soil health.

The longevity of a farm is closely connected to the health of its soil.

Carbon plays a major role because it supports biological life within the soil. Bacteria, fungi, and other organisms interact with plant roots and influence how the plant grows, accesses nutrients, and prepares for stress.

This is why soil health cannot be reduced to one product or one application.

It is a system.

Keeping living plants in the field longer can support biological activity. Cover crops may fit some operations. Better water management can improve soil conditions.