Mother Nature has reminded us this spring that the seasonal “average” weather isn’t always what she decides to provide us. For most of the spring, especially through the Midwest and Mid-Atlantic regions, the up and down temperatures have stressed even cool season turfgrass. After a warmer winter period and above normal temperatures in March that encouraged spring green… prolonged periods of overcast, cold and damp followed. Cool season is stressed, but bermudagrass is REALLY confused. Bermuda in many situations is acting like it just “out of gas” to be able to regenerate or transition out from ryegrass overseeding.
But we are seeing some very different bermudagrass results with regeneration and/or transition. Some bermudagrass fields are fighting back strong now that we are into May, yet some continue to face challenges. But why? Temperatures across through the Midwest and Mid-Atlantic came up early to support bermudagrass to pull out of dormancy early. Shouldn’t it be growing actively by now, even with the cool and overcast?
Literally, it really is just “Out of Gas”!!!
The lack of full dormancy and early spring green up, things we thought were good, are actually what is leading to the bermudagrass being “out of gas”. It can even be worse on bermudagrass that was kept under grow covers most of the winter. The covers provided temperatures for the bermuda to continue to grow. But we now are understanding that temperature alone is not enough. The importance of light for photosynthesis in bermudagrass has been overlooked. The short days w/ a low sun angle through the fall, winter and spring have a bigger impact on bermudagrass growth than we have ever realized.
Light Requirement For Bermudagrass: Bermudagrass requires more than for cool season. On average, bermudagrass varieties requires around 35 mol/ day of light for photosynthesis to produce the required energy for normal plant processes. In Raleigh-Durham, North Carloina in full sun (no winter damaged tissue or ryegrass overseeding producing shade), the sun provides (See chart below for entire year):
Fall: Sept 10 to Oct 8 average: 39.5 mols/ day
Oct 8 to Nov. 5 average: 28.1 mols/ day
Nov 5 to Dec 3 average: 19.9 mols/ day
Winter: Dec 3 to Dec 31 average: 19.3 mols/ day
Jan 1 to Jan 29 average: 19.3 mols/ day
Jan 29 to Feb 26 average: 26.8 mols/ day
Feb 26 to March 26 average: 33.4 mols/ day
Spring: March 26 to April 23 average : 46.3 mols/ day (FINALLY above 35 Mol/day!)
April 23 to May 21 average: 48.2 mols/day
From mid October until the first of April, even in full sun, photosynthesis can not produce enough energy to support regular bermudagrass plant growth. Thats over 5 MONTHS! For bermudagrass further north in somewhere like Kansas City, the light required for healthy growth would lack for nearly 6 months. Newer varieties of bermudagrass like Latitude36 and Celebration require less light than the 35 mols/ day, so we see them sustain growth later in the fall and earlier in the spring. But overall, the light for photosynthesis just isn’t there.
So what? Why does this matter to bermudagrass? When Mother Nature provides warmer temperatures, or when we manipulate the growing environment with grow tarps, bermudagrass grass sustains green and produces growth. But because photosynthesis isn’t producing energy to keep up with that growth, late season or early spring growth, the energy reserves of the bermudagrass are burned up and the plant goes into stress and starvation mode. Some fields we have this spring have actually went dormant when they were green in January and February. Or fields that were growing in March have slowed now even into May because of the continual overcast, cloudy and wet conditions.
Now that we understand the cause, for the short term, how do we find a solution? Follow we want to share what seems to be some of the pillars of the strong bermudagrass regeneration and transition:
Get light to the bermudagrass plants: We have established the problem of the lack of light and the need for energy production. Step 1… get light to the plants! This means:
a. Lower mowing height and increasing mowing frequency. Especially on a bermudagrass field that is overseeded. In non-overseeded, mowing low (down to 1/2” if possible) will help clean out all the dead or winter damaged tissue and promote green bermudagrass to push up through.
b. Clean out/ Open up the canopy to get sun down through. Something as simple as brushing or dragging with a steel drag can open up the canopy. Verticutting, core aeration, or Universe Fraze Mowing can clean out and open up the canopy as well. Avoid topdressing with more than 1/8” of material… we want to promote light to the plants, not increase the barrier.
c. Supplement support for energy production from bio-stimulant products: Technology in plant feeding products allows us to provide the stressed bermudagrass with the amino acids and sugars that it needs to support photosynthesis for energy. A range of patented, scientifically engineered products existing to do this so all the stress isn’t on the plant and photosynthesis. Key, patented products were are recommending for stress relief and photosynthetic support include a combination from Floratine Products Group:
- Protesyn: Formulation of amino acids, proteins, and carbohydrates. Equate Protesyn to a sports drink and/or some liquid sunshine. Helps with lack of energy and stress!
- Knife Plus: Micronutrient product combined with a hormone loading for support of plant systems. The micronutrients cover the range for the essential building blocks for photosynthesis
- 5.0 Cal: Blend of calcium and simple and complex carbohydrates to support the turfgrass plant during stress periods. The calcium and sugars mirror what is produced during photosynthesis.
The fields we are seeing in the strongest condition are receiving supplemental bio-stimulant applications to support energy production. Simply… The applications are supporting plant processes to keep the plant from running out of gas!!
d. Avoiding N to drive growth, Instead using hormones to push natural, healthy growth: With getting sunlight to the plants and reducing plant stress by using plant feeding technology, its time to push the bermudagrass to start to grow and recover. Go go go! But another theme of the best fields we are seeing currently are NOT turning to just nitrogen to push growth. Historically, spring time growth and bermudagrass fill in comes from simple applications of 46-0-0 and 21-0-0. But we now know that excessive nitrogen drives unhealthy growth and burns up energy reserves. Yes, we just built up our energy reserves! Lets not burn through them already. Instead, for a granular fertilizer, turn to an organic product to feed soil microbes or a Poly coated product such as Polyon to give you control of release. Then turning to a hormone package to increase cell division and drive healthy, natural growth at this point in time. Temperatures, soil and air, continue to be low. Even if you are set on using N for your re-grow, its too cold for bermudagrass to metabolize N in the Midwest and Mid-Atlantic. Hormones, in combination with the energy support we discussed previous, really is the best ticket to get strong re-generation and transition through ryegrass in this stressful time.
Recommendations on products? We recommend our clients turn again to Floratine Products Group for some of their patented bio-stimulant products:
- High 5: Warm-season grass specific nutrient product with hormones and micronutrients
- Per4Max: Hormone and nutrient product designed specifically to increase GA production to promote cell division for bermudagrass to spread rapidly
– With that combination, a potassium phosphite product also is helpful to support energy production along with .05 lbs/ of true foliar N in the spray.
De-compacted the soil!! De-compacting soil is the #1 key cultural key in the successful bermudagrass regeneration and transitions observed this spring. Wet soils compact more quickly from play than dry soil. These consistent wet conditions have led to some extreme compaction conditions. Those compacted soils need opened to:
Allows air into the soil profile, promoting both soil microbes and bermudagrass roots. The soil air and microbial activity on a de-compacted soil are essential for support growth
Allows water to move down through the soil profile faster. The water moving through reduces rain cancellations. It also allows air to come back into the soil faster. Where there is water, there is no air. Once the water can move through and air is back into the soil, both soil microbes and the bermuda roots can be stronger.
Ultimately, the lessons of a challenging spring here in 2016 will help us avoid the same challenges in the years ahead. Because of the mild winter through the Midwest and Mid-Atlantic, it was assumed that the spring and summer would be much easier with winter kill totally avoided. But the damage done from semi-dormant bermudagrass attempting to grow when it is typically dormant may cause just as many challenges as winter kill could. But overall, with as aggressive as bermudagrass can be, as soon as you are able to 1) get light to the plant and 2) supplement to support energy production, the plants will recover and begin to grow. Then at that point you can 3) push healthy, strong growth with hormones and utilize slow release N to support the growth process.
And remembering the key, none of it works at all on a compacted soil! Fields need to be used, we just have to respond in new and different ways to support them. Even when Mother Nature doesn’t want to cooperate.
Keep up the great work, and share your examples of success with us if you are having them! Cheers to #GrassCanTakeMore™!!!
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VERY NICE AND CLEAR! Even for this non-turfgrass expert! Nature is always full of surprises but adaptability is key!- finding out what’s actually going on instead of guessing is both fun , intellectually exciting and leads to solutions. Often we already have solutions in our “toolkit” if we only pay attention. An allegory for people’s lives. A great structured way to teach schoolkids about living systems.