Sod on Plastic Establishment Practices for CoolSeason

Grasses

BY JOHN N. ROGERS, III, JACKIE GUEVARA, RYAN BEARSS, JAKE KILBY AND EVAN ROGERS MICHIGAN STATE UNIVERSITY

How the MTF funding will be used to support project(s): Support funds will allow researchers to gather sod on plastic (SOP) establishment data at various Michigan locations for the benefit of Michigan sod producers.

Background of the study:

Sod grown on plastic is a method of sod production where turfgrass is established on a thin layer of growing medium spread over plastic sheeting.

BENEFITS OF GROWING SOP

• Complete control of the growing medium, preventing soil layering issues.

• Ability to harvest the whole rootzone without damaging the roots, avoiding transplant shock during sod harvest and installation.

• Faster establishment rate, reducing production time from 18 months to 4 months.

• Facilitates sod production on non-arable lands (e.g., concrete, parking lots).

Project update:

The researchers hypothesized that the production of Kentucky bluegrass (KBG; Poa pratensis L.) sod grown on plastic could be accelerated by incorporating small amounts of perennial ryegrass (PRG; Lolium perenne). In 2022, a study was established to evaluate the effects of various KBG and PRG seeding ratios on the harvestability, and stability of sod grown on plastic.

This study was conducted from 19 May 2022 to 23 September 2022 at the Hancock Turfgrass Research Center, East Lansing, MI. Treatments consisted of six Kentucky bluegrass: perennial ryegrass seeding ratios (100:0, 98:2, 96:4, 92:8, 84:16 and 0:100) sowed at 20 seeds inch-2. To quantify sod harvestability and stability of seeding ratios, tensile strength and shear strength was measured 18 weeks after seeding, respectively.

Key Points Learned to Date:

• Incorporating PRG improved sod harvestability and stability, which supports the hypothesis that adding PRG into a KBG sod could hasten sod grown on plastic production.

• PRG sod (0:100) had the highest tensile and shear strength (Figure 1 & 2) demonstrating that PRG sod on plastic production is feasible.

• To further validate these claims, this experiment will be repeated in 2023.

Expected methods and results:

To further substantiate our observation about the harvestability of PRG sod grown on plastic, researchers will conduct an additional study that evaluates PRG sod grown on plastic at different periods of establishment. This study will be conducted at the Michigan State University Hancock Turfgrass Research Center and DeBuck’s sod farm. Perennial ryegrass sod grown on plastic will be harvested at various periods (2, 4, 6, 8, 10 and 12 weeks after seeding). Tensile strength and shear strength will be used to quantify sod harvestability and stability, respectively.

Grad Student(s) Involved: PhD Candidate Jackie Guevara, MSc student Jake Kilby and Research Technician/ PhD Candidate Ryan Bearss

Benefit Group:

In the short term, these experiments will benefit prospective Michigan Sod Producers interested in entering the sod on plastic market. In the long term, these data will benefit international sports associations (FIFA, MLS, NFL, etc.). Spartan Stadium will also benefit from these endeavors by gaining access to reliable sources of sod on plastic for annual stadium re-sodding.

Project Images:

(a) Existing turfgrass in the area was killed and fraizemown to set up a bare soil area for sod grown on plastic establishment. (b) The area was rolled and levelled. (b) A white plastic was laid down on the area. (d) Sand (oneinch depth) was topdressed on top of the plastic sheet.

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PROJECT NAME:

Effects of dried leaf matter on weed populations and soil health

BY THOMAS A NIKOLAI PHD, ERIC J. GALBRAITH, MIKE RABE MICHIGAN STATE UNIVERSITY

How the MTF funding will be used to support project(s):

Support funding will allow researchers to evaluate weed control and soil effects from dried leaf matter mulched into turfgrass plots. Three trials testing mulching effects at various rates and heights of cut will be conducted; Lawn Height Maple Mulch, Fairway Height Maple Mulch, and High-Rate Mixed Mulch.

Project update: duration: duration:

Figure 4. Measurement of sod harvestability (tensile strength) using a Calrochan Sod Puller at 18 weeks after seeding (September 2022) at Hancock Turfgrass Research Center, East Lansing, MI

Estimated project duration: Studies started in Spring 2022 and will continue through Summer 2024.

Measuring sod strength of Kentucky bluegrass and Supina

Measuring sod strength of Kentucky bluegrass and Supina

References:

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Sorochan, J. & Rogers, J. (2000). Measuring sod strength of Kentucky bluegrass and Supina bluegrass. TurfGrass TRENDS. July. 8[9](7): p. 6-9.

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Three experiments have been initiated at the Hancock Turfgrass Research Center, East Lansing, MI. In 2021, two maple leaf mulch trials were initiated: one on lawn height turf [Lawn Height Maple Mulch] and the other on fairway height turf [Fairway Height Maple Mulch]. In 2022, a third trial was initiated on lawn height turf [High-Rate Mixed Mulch] using a much higher rate of mixed species mulched leaves from silver maple (Acer saccharinum), red maple (Acer rubrum) and eastern cottonwood (Populus deltoides). We have been collecting soil temperature and volumetric water content data throughout the winter when weather conditions allow. Analysis is in progress for the fairway height trial with a focus on evaluating effects on Poa annua. We expect it may take a few years of applications to see potential differences. Mulch applications for all three trials were made November 28, 2022.

Key Points Learned to Date:

• Mulching leaves into turf in the fall can significantly reduce broadleaf weed populations in spring and enhance green-up.

• Lawn height treatments receiving 20 lbs of dried mulch in November of 2021 showed significantly less dandelions and dandelion flowers than the non-treated control in May of 2022 (figure 1).

Results:

Results for the lawn height trial initiated in 2021 have corroborated findings of previous, related research conducted at MSU. Treatments receiving 20lbs of mulch in November of 2021 showed significantly less dandelions than the non-treated control in May of 2022.

Project Images:

Grad Student(s) Involved. None

Benefit Group: These experiments will benefit home lawn care operators, golf course managers, municipalities and homeowners. Research could lead to better cultural practice recommendations. If mulching in leaves during the fall improves soil health and controls weeds, then seasonal herbicide and fertilizer inputs could be minimized and financial costs cut.

Estimated project duration:

Key Points Learned to Date:

• The PGR Proxy is the primary tool used to suppress/decrease annual bluegrass seedheads and numerous golf course superintendents apply the product 1-3 times starting in the late fall prior to seed head production in the spring. However, some superintendents believe the suppression with the product is not as good as it used to be while others are curious if tank mixing with other products may enhance the suppression. Treatments in this study were chosen to address those concerns.

Expected Results:

Expected Results:

Name: How the MTF funding will be used to support project(s): update:

Estimated project duration: Studies initiated in fall 2021 and will continue through fall 2024.