Turfgrass Cultural Practices
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“Turfgrass culture is the science and practice of establishing and maintaining turfgrasses. The major areas: mowing, fertilizing, irrigation, cultivation, establishment, and disease."
James B. Beard.

    Mowing

Is the cutting action in which a small area of the leaf is removed. The grassplant can handle mowing because the leaf growth happens at the base of the plant. Photosynthetic process happens at the leaf tissue by taking light energy and converting it into hexose sugar that can be moved throughout the plant. It’s very important to have your greensmower sharp and the reel to bedknife contact at their best, because removing the tip of the grassplant is the site where pathogens can enter. If this area is cut with a dull or a poor set up (reel to bedknife contact) you will get a tearing or pulling of the grassplant. This could lead to “Pain and Disappointment” it will be a toss up between you and the green on who gets what. Put yourself in a situation where you and the green will be successful, keep the mower clean and in good operating condition.


    Fertilizing

Can be applied by liquid spray or granular form. Nutrients can be absorbed in the plant through its leaves, stems, and roots. Most water & nutrients uptake happens at the root system. A fertilizer application is to supply nutrients to the grassplant to maintain color, health, and vigor. To keep nutrients in the soils at the right levels for the grassplant to maintain health and growth a “light & frequent” or “spoon feeding” program is best. If a soil test can be done, this will help to set up future fertility programs and give you a better understanding of what the plant needs. There are 16 essential elements of nutrition for the grassplant with nitrogen, phosphorus, and potassium being the main three. Nitrogen helps with color, growth, shoot density, and with reestablishment of the turf from disease or damage areas. Phosphorus helps with establishment of seed and sod and should be available close to the surface to stimulate root growth. A high level of phosphorus quickens maturity. Potassium helps with building a strong root system, drought, heat & cold hardiness, and wear tolerance. I have just shed a little light on this subject, there is much more information on fertilizing and the effects it has on the grassplant. If there is any doubt or questions then more reading and research should be done before a fertilize application is done.



    Watering

Is done to maintain the grassplant health and vigor. Watering a putting green to maintain health and growth can be difficult. If watering is too infrequent then wilting or “hot spots” will develop. This will bring stress to the plant, and could lead to the development of hydrophobic soils. This will lead to hair loss and the making of an ulcer for you, because you will want to add water to this area to bring the turf back. Now that the turf is stressed and wet with warm temperatures you have helped create the ideal condition for disease. The use of wetting agents will help you fight wilting. Too much watering can lead to, short root development, scalping, soft putting surface, and disease. Ideally you want to water early in the morning (4:oo a.m. to 6:oo a.m.) and just enough to maintain the health of the grassplant. One way of knowing the moisture level in the root zone is to use a probe, this way you can see if there is enough moisture or if you need to add some. Then based on what you see and what your local weather is going to be you can make the decision on watering the green. If the weather condition in your area has been hot with wind and this weather pattern will be continuing, syringing the green can help reduce hot spots from developing.

Hydrophobic Soil – Soil microbes leave a thin film that coats the soil particles. Upon drying the thin film resist the absorption of water, robbing the grassplant of much needed moisture.

Wetting Agents – Are surfactant that helps to lower surface tension which increases the soil particles ability to absorb water. Also helps to spread the water more evenly over the soil particle. Using wetting agents, you will have to reapplied several more times throughout the growing season, but is well worth it.

Syringing – Is applying a light amount of water to the grassplant to reduce wilting or hot spots from developing, and cooling the turf canopy. This can be done with a hand held hose or 1-2 minutes with an irrigation system.



    Cultivation

Is a selective mechanical method of improving established turfgrass. Aerating is a method of using hollow tines to pull up a core or solid tines not to pull a core. You aerate a putting surface to improve air and water movement in the root zone, to reduce compaction, reduce organic matter build up, and to manage the mat layer. There are two methods of aerating a green. #1 you pull a core and remove them all from the surface. Then you topdress with dry sand making sure all the holes get filled in to the top, then water. #2 is to topdress with dry sand first, and then aerate the green. With the cores sitting on the surface use a brush or drag a mat to break up the cores, by doing this you are mixing the cores, organic material and the new sand together while filling in the holes. Once the holes are all filled in, remove all excess debris from the green, then water. You would use this method if you are satisfied with the mat layer before you aerated, which ideally should be around ¼”. Before you start to aerate your green, pull the cup out and fill the hole with sand to the top. By doing this, it will help to keep the hole from getting damaged and collapsing in on it’s self from the tines going up and down. When you are finished you can remove the sand with your hand and either put the cup back in or cut a new one.




    Topdressing with Dry Sand

You use dry sand because it’s easier to work with when moving it around filling in the holes on the putting surface. If you use wet or damp sand it will “bridge” the holes meaning, the holes will appear to be filled to the top, but when the sand does dry it will fall to the bottom of the hole, leaving ½ to 3/4 of the hole exposed. This will lead to all kinds of problems, so an extra effort will be needed to go back and fill all the holes. To make this chore a little easier on you and your back use dry sand to insure all holes get filled in and to eliminate the “bridging” effect.




    Mat or Thatch?

Thatch is a layer of living and dead organic matter that develops between the crowns of the grassplant and the soil surface. Thatch is only organic material and is detrimental to turf health, because organic creates surface tension that restrict air and water movement through the soil. Mat Layer is living and dead tissue and sand mixed in. The sand incorporated within bridges and keeps this layer porous. This mat layer gives a putting green its resiliency and shot holding ability. Thus one major reason for “light & frequent” topdressing in maintaining a mat layer and not a thatch layer. You want to have the mat layer ideally at ¼”.

Charles “Bud” White
USGA Agronomist.

Too much mat that’s between ¾” – 1” will create a favorable condition for disease, soft putting surface, scalping, pests, and will slow air & water movement. Excessive mat can lead to over watering, because roots begin growing into the mat, the turf becomes susceptible to drought damage. So more water will be needed to help bring back the turf area, with the extra watering the mat will swell and act like a sponge. When the mat is saturated then it will release the water into the root zone, this will make for a soft putting surface. The weight of the greensmower is more then the soft surface can handle, this is where the scalping takes place on the green. Excessive mat will give you grief with your fertility, because it will hold on to much of the nutrients and release a small percentage, making for an inconsistent distribution to the grassplant.




  Ways of Maintaining Mat


Aerating, vertical mowing, and topdressing with straight sand are great ways of controlling and maintaining mat. If there is excessive mat in the green “heads- up” should be given when aerating or a deep vertical mowing, because it can be destructive to the grassplant. The roots are in the mat so plants can tear out easily. Early spring or late summer is best to aerate, because of the cooler temperatures allowing for healing and recovery time. A light and frequent topdressing program for the growing season is best for the green. Not only will this help to maintain a desirable mat layer, but also improve and smooth the putting surface. Topdressing a green is applying a thin or a heavy layer of sand on the putting surface. It can be worked into the turf canopy by using a brush or dragging mat, if it is light enough, can be watered in. Some of the reasons for topdressing are, maintaining a mat layer, smoothing the putting surface for a better ball roll, filling in low areas, if establishing a new green from seed, cores or sprigs, applying sand light and frequent will quicken density. Be careful when temperatures get to 25 c (78F) or hotter, sand will radiate the heat from the sun and cook the top ¼” of you’re green.

Verticutting is a deep cleaning action of the grassplant on the putting surface. Vertical mowing is a mechanical action that helps to remove excess organic material. Blades sit ¼” to 1.5” apart on a disc, rotating through the turf bring up thatch and opening up the canopy to allow the turf to breath. Once the putting surface has been cleaned off of all debris, topdressing with straight sand is beneficial.


Groomers are a light weight action of a verticutter. The vertical blades are thinner and the cutting depth is less. The Groomers concentrate on the growing areas and the tips of the grassplant. The action of the groomer is less drastic and allows the turf to recover quickly and look some what untouched.


Deep tine holds 30 1/2" diameter tines that are 12" long. You can adjust how much length penetrates the ground, we usually go around 6". For the rough areas we use 10 tines that are 3/4" in diameter and also 12" in length. Again you can adjust the length that penetrates the ground.


If the mat layer on the fairways is at the right thickness, then solid tine aeration is the way to go. There are no cores to mat in or to clean up which is a time saver. You topdress the fairway first and then punch, if you punch first and then topdress the tractor and Ty – Crop tires would be driving over the holes and collapsing them, making it all most impossible to work the sand into the holes, not to mention the ruts that would be created.


Metal mat being pulled by a utility vehicle to move sand around into the holes on the fairway. This is an effective way to get this stage of the topdressing program done.


You can see how much work this operator has in front of him on this par 5. It will take a few hours to work the sand into the holes.




    Establishment of Green

When starting a new turf project following all proper construction steps will ensure that the project will be successful and bring fulfillment. If you are going to invest time, money, and lots of labour there are no short cuts. Site preparation is very important whether it’s a green or another turf site. Before you start digging you want to look at drainage, irrigation, mounding, bunker location, sun location for the green, and wind movement. In the winter time the sun sits lower in the sky with longer nights and shorter days. Trees that are close to the green will throw long shadows, this will slow frost melting and wetness leaving the turf blade. You want the green site to be free of all rocks, wood, and any other debris. When shaping mounds, bunkers, or other grades make sure its maintenance friendly. If the grade is too steep scalping could happen plus holding moisture will be difficult. When building the subsurface of the green keep in mind that the surface will mirror the subsurface. Any mounds, slopes, or contours that are to steep will give you grief when mowing at ¼” or lower. Shaping a green should be gentle and flowing. Drainage on the subsurface of a putting green should be herring bone style, this works well at removing excess water. In some backyard greens the pea stone layer can be skipped, because of budget or time and this is fine. One of the main reasons for building a putting green with high sand content and subsurface drainage is for rapid removal of excess water. As soon as playability of the greens is reached after a heavy rain, the sooner the golfer gets to pay& play. If building a bunker, drainage should be done. Water sitting for a long period of time will bring all kinds of problems and disappointment.

When shaping the rough surrounds of the green the use of swells and other contours can help in surface drainage, moving excess water away from the green. When preparing the root zone mix, having a high sand content will speed up drainage for the green. A small amount of organic material blended throughout will help with water retention and nutrient availability. Whenever possible buying already made root zone mix is best because of the homogenous mixture, but if not in the budget then mixing should be done off site. This will ensure no contaminants will get mixed in and give you the opportunity to do a really good blend. The soil in the surrounding areas of the green should be clean of any debris. Roto tilling the soil will relieve compaction and make the soil easier to work with. If there is a high clay content removing as much as possible and adding sand will improve the area. Once the rough area has been clean, tilled, shaped, rolling is the next step. Rolling the root zone mix or the surrounding soils will help to firm and show levelness of the surface. After the first roll is done go back and fill in the low areas. Rake material from the surrounding area and bring it into the low spot. When you are satisfied that all the low area have been filled in, watering and rolling these areas again will ensure firming up the soil and less chance of settling in the future.




    Establishment: Surrounding Areas

A light rake over the soil surface is what’s needed to prepare the surface for seed, sod, or cores. Starter fertilizer is next (high phosphorus number) 2 lbs per 1000sq.ft will aid in the germination process. With the starter fertilizer applied and the seed or cores spread out, another light rake in the opposite direction is beneficial for germination. The second raking will create a tumbling action mixing the soil, fertilizer and the seed or cores together, giving it a higher germination rate. This will speed up establishment of the turf. If sod is being used, after the final roll do a light rake in any direction, put down the starter fertilizer, then rake in a different direction , then lay down the sod. Keep the edges tight together this will speed up establishment and prevent the edges from drying out.

The keys to good germination are moisture & temperature. You want to keep the seed moist, no puddling or moving water from heavy irrigation. Moving water will pick up the seed and move it else where, leaving that area with poor or no germination. Light and frequent with watering is best in the germination stage. Once growth on the green has reach ¼” in height watering should be reduced and cutting should start. Cutting stimulates the grassplant and will help with density. The first 8 to 10 cuts should be without a bucket, this will help form the mat layer. With the grassplant actively growing from all the water and nutrients that is being supplied you don’t want to have a few days go by without cutting. If you do, there will be a bigger grass blade going down on the green. The green is better off with a small amount of clipping going down. This will be the time to start a “light& frequent” topdressing program, it will help with producing a smooth grow – in. Using dry sand with a spin type or a drop spreader works best when applying a thin layer of sand to a green. Once the green has reached approximately 70% to 80% coverage, you can start thinking about lowering the height. Do not take more then 1/3 off of the grassplant at one time, this will bring on stress and set the turf back. Let’s say you have been cutting at ¼” and there have been no problems. The next adjustment will go down to 7/32”. If there is no scalping or damage from the greensmower stay at that height for at least 7 to 10 days. Keep a close eye on the turf, looking for any signs of stress, if this is going well after 10 days, then lower the height without taking more then 1/3 of the grassplant off. Stay on this schedule until you have reached the height that you want for the green. If you are scalping in some areas, fix them right away. When you go back to mowing raise the front of the mower over these areas until they have recovered.




     Disease

This is one of the hardest areas of maintaining a putting surface at ¼” or lower during the summer’s months. There are so many elements that can bring on disease, so you want to do everything you can to put your green in the best possible situation. This would include a great sun location, think about where the sun will be during the winter months. If you have snow that stays all winter there is not much you can do, but with the green in a good location coming out of winter the green will drain and dry out faster with sun on it. You want to have good air movement, this will help in drying off the grassplant and provide a better growing environment. Picking the right variety of turf for your putting surface should take some time and research. You want a variety that will do well in your area and climate. Once you have selected the turf you want, use the internet and read books on diseases that will affect that variety of turf that you have selected. There will be a learning curve for the new greenkeeper, so it’s important that you get as much information as you can to lessen any mistakes. This website is great for the beginner www.putting-greens.com then click on “green forum”.

Murphy’s Law will be with you every step of the way, making your life miserable on your project testing your commitment, he wants to know if tearing the hell out of your backyard is worth all the glory of a little white ball. Well, when you are sitting back in your chair at the end of the day with every part of your body hurting from making your dream a reality, take a long draw from your cold beer and look up at the sky and yell right at him, FIFO! (Fit in or F%*k Off) the feeling that rushes through you will be gratifying, but will be short lived. He is a repeat offender and will retaliate when yelled at, so you will need to perform this sanity check repeatedly throughout the building and maintaining of your turf project, good luck – Rob.




    Links:

A great article from Oregon State University on Poa annua


Turf Grass Diesease from Penn State University