Since a large part of the sports turf manager's job is to manage high traffic areas under constant renovation, the practice of syringing can make all the difference between a successful seeding and a failed seeding operation.
Syringing: key to successful seeding
“Syringing” refers to the practice of lightly watering turf. In golf course management, syringing is a common practice done during summer to cool the turf canopy, prevent turf wilt, and remove dew or exudates from the leaf as a means to avoiding turf diseases. In sports turf management, the term syringing is used more often in reference to seeding and moisture management during the seed establishment phase. Since a large part of the sports turf managers job is to manage high traffic areas under constant renovation (between hashes, goal mouths etc.), the practice of syringing can make all the difference between a successful seeding and a failed seeding operation. Thus, the purpose of syringing seed is to make sure that the seed coat stays moist until it has germinated.
For seeds to germinate, they need moisture, oxygen, warmth and sometimes light. Moisture is the key. If there is some moisture stress/drought during early germination, when the seed is taking on moisture and the tissues swell (imbibition) then it may not damage or kill the embryo. If however, there is drought stress during the later stage of germination, when there is cell division and growth, then the seed is more likely to die and the renovation fails. It is critical then, that the seed stay moist until green grass cover is visible. With fast germination turf species like annual and perennial ryegrass, the germination period is around 3-5 days, tall fescue is around 7 days and Kentucky bluegrass is 7-21 days, depending upon the variety.
Keeping the seed in a constant state of moisture until green tissue is visible requires the sports turf manager to syringe the seed several times daily. There is not hard and fast timing on the amount of syringing cycles needed as it depends upon the daily weather conditions. On sunny, windy days (high ET rate) seed may need syringing as much as 5 x per day, while on cloudy, calm days (low ET rate) seed may only need to be syringed 3 x per day. An example of a syringing cycle could be: 9am, 11am, 1pm, 3 pm, and 5pm. During late June, July & August when days-lengths are long, a 7pm cycle may also be required.
Syringing is NOT the act of replenishing water lost through ET or applying water deep & infrequent to encourage growth. Syringing is a light application made purely to wet the seed. Syringing is done either by a quick 1-2 cycle rotation of an irrigation head (with an in-ground/pop-up automated irrigation system) or by hand. Syringing by hand is a common practices and involves light watering with a hose equipped with a syringing nozzle. The purpose is to lightly wet the weed, not blast it off the soil surface, so a syringing nozzle on the end of the hose is essential.
Ideally, to prevent seed movement and soil erosion after a heavy rain, the seed should also be lightly covered with either (a) topdressing sand (b) a growth blanket (c) hydro-mulch, or (d) straw. A cover helps to retain moisture & heat and prevents seed & soil movement until the seedlings are established. It might also deter field users from using the area until the renovation is complete.
* New seed should ideally be covered to prevent movement & erosion
* Seed should be syringed several times daily until green grass cover is visible
* Syringing should be carried out with a hose equipped with a nozzle, or a short cycle (1-2 head rotations)with an automated irrigation system
* Kentucky bluegrass seedings typically fail more readily than more faster germinating species because the syringing program can take up to 3 weeks. Syringing requires a commitment from someone to make sure the seed stays moist for as long as it takes during the establishment period.
Posted by Pam Sherratt & Dr. John Street on www.buckeyeturf.osu.edu