Turf Management

Jason Lanier, extension educator with the University of Massachusetts Turf program, shared an overview of why this is so important in an article in UMass Turftalk. The article enumerates the many benefits of core aeration.

Relief of Compaction 

– Compressive forces such as foot or vehicle traffic can lead to dramatic reductions in total pore space of the soil. Compacted soils provide a challenging growing environment that restricts infiltration and drainage of water, gas exchange with the atmosphere, and root growth. Removal of soil cores through aeration is an important tool for restoring some pore space to the root zone and providing relief from these negative factors.

Improved Gas Exchange 

–Turfgrass root tissues require a sufficient supply of oxygen for respiration and growth. Beneficial soil microorganisms also require ample oxygen for proper functioning and robust population numbers. Aeration creates means for gases in the soil to be more effectively exchanged with the atmosphere. As a result, this promotes the cycling out of less desirable carbon dioxide the cycling in of more desirable oxygen. Also, aeration promotes better moisture infiltration and drainage, reducing the potential for prolonged soil saturation and associated oxygen inhibition.

Improved Microbial Activity 

–Like turfgrass plants, soil microorganism populations normally benefit from aeration. As noted above, aeration promotes better gas exchange, improves root zone water relations, and positively impacts the overall growing environment. Healthier microbial populations perform myriad functions including the breakdown of thatch and organic matter, and the recycling and retention of nutrients in the turf system.

Management of Thatch 

– Thatch typically accumulates when resilient plant tissues, such as stolons and rhizomes, are produced faster than microbial populations are able to break them down. Improved soil conditions from aeration help to ‘tip the scales’ in favor of microbes. Also, the rate of thatch buildup is better controlled as a result. Hollow-tine aeration physically removes significant quantities of thatch, which disrupts the layer. In addition, it creates a greater surface area for more efficient degradation.

Improved Moisture Infiltration 

– Because aeration helps to break up and reduce thatch and mat layers, and to disrupt any existing surface crusts, better site permeability and better infiltration of moisture into the root zone frequently results. More effective infiltration translates to more efficient use of irrigation and natural precipitation and reduces the potential for negative conditions such as puddling and runoff.

One of the key merits of core aeration that is sometimes overlooked is the idea of ‘access’ to the root zone. Bear in mind that turf is a perennial system typically maintained in a relatively undisturbed state over a period of several years. This means that the most valuable time for incorporating fertilizer, liming materials and other soil amendments into the root zone is at the time of establishment or during a wholesale re-construction event. While not a replacement, proper aeration is the next best avenue for ‘opening the soil’ and transmitting amendments and other materials into the root zone. Aeration also helps to promote seed-to-soil contact for more effective overseeding, which can also help with recovery from the disruption that aeration creates.

While several aeration events per year may be appropriate for higher traffic areas, especially on golf courses or sports fields, once annually is an appropriate guideline for many lawn and grounds areas. However, lower maintenance turf areas may be aerated even less frequently. It is important to apply aeration based on need and specific management goals. In fact, research has demonstrated that aerating too frequently, especially at similar depths, can create a ‘cultivation pan’ in the soil profile over time.

Thatch is a tightly intermingled layer of living and dead stems, leaves, and roots which accumulates between the layer of actively growing grass and the soil underneath. Thatch is a normal component of an actively growing turfgrass.  As long as it is not too thick, it can increase the resilience of the turf to heavy traffic. In addition, thatch develops more readily on high-maintenance lawns than on low-maintenance lawns.

An excessive thatch layer can restrict the movement of air, water, fertilizer and other materials to the roots. This is all necessary for healthy, vigorous turf growth. For reference, an excessive layer would typically be more than 1/2 to 3/4 inch, depending on the situation. Since thatch greatly restricts the permeability of air and water, the grass plants tend to to root within the thatch in an attempt to obtain these resources.  Thatch is a poor growing medium and this process reduces the overall drought resistance of the turf. Furthermore, if the thatch dries out, it cannot be rewetted easily. Even if the thatch stays moist, it can harbor fungi that cause turf diseases. When certain temperature and moisture conditions arise, a disease infestation can kill the already weakened turf.

The overall effect of a thick thatch layer is an unthrifty lawn which does not respond well to management practices. In addition, adverse weather conditions and pests easily injure a thick thatch layer.

Our team uses mechanical means to reduce thatch that has accumulated to an excessive level.

Fall is the best time to grow cool season grasses in New England such as rye, kentucky bluegrass, and fescues. Here is why:

• The combination of warm soild, moderate day temperatures, and cool evenings encourage fal germination.
• Summer time temperatures can stress a new lawn, inhibiting growth
• On average, we recieve more rainfall in the fall, keeping the soil moist, producing an optimum growing environment while reducing the extra watering on your part
• Summer weeds such as crabgrass will easily crowd out new lawns that have been planted in the spring or summer. There is less competition of weeds in the fall, giving grass a better chance