Magazine - Evaluation of Sanoplant Soil Amendment Trials

By John Robertson in Consultancy on 12th Jul 2010 12:00

The purpose of this trial was to evaluate the effects of incorporation of Sanoplant™ into a sand profile on a sand based putting green using a medium washed sand.

1. TRIAL OBJECTIVE
The purpose of the trial was to evaluate the effects of incorporation of Sanoplant™ into a sand profile on;
a:  Improving the water retention (volumetric water content) of a sand golf green construction using Sanoplant™ compared to the industry standard of using peat moss.
b: Reducing water requirements.
c: Reducing the incidence of localised dry patch.

2. METHODOLOGY

2.1 Trial Location
The trial was conducted at Chisholm Institute of TAFE, Boneo Road, Rosebud.

2.2 Climate data for trial site

# Please refer to appendix D for detailed maximum daily temperature and daily rainfall data.

2.3 Sand Selection and Construction Type
The trial was constructed as a sand based putting green using a medium washed sand supplied by Rocla Quarries located in Langwarrin. Appendix A details the physical characteristics of the sand, with the main parameters being that the sand has a moisture retention of 12.9%, which is less than the minimum volumetric water content specified by the USGA (i.e. specified to be between 15 - 25% v/v).

2.4 Treatments
The treatments were as follows; Treatment 1: Sanoplant™ at 1.5 kg/cubic metre. Treatment 2: Sanoplant™ at 3.0 kg/cubic metre. Treatment 3: Peat moss at 10% v/v. Peat moss represents the standard amendment product for increasing soil moisture retention. Treatment 4: Control – Unamended sand.

2.5 Replicates
The trial was set up as a block design with three replicates – (randomised block design). Refer to Appendix B for the plot layout.

2.6 Plot Size
2 metres x 2.5 metres

2.7 Trial Establishment and Management
The trial site was constructed as a golf putting green as follows;
a. Sand Depth: 300 mm deep sand profile consisting of 295 mm of amended sand with a 5 mm unamended sand capping layer.
b. Sand was laid on a permeable sub base to ensure there was unrestricted drainage.
c. Site prepared and leveled and the amendments applied to the surface and tilled into the full depth of the profile.
d. A 5 mm capping layer placed over the Sanoplant™ amended plots.
e. Fertilisers applied prior to planting as follows;
# NPK (8:10:10) at 4 kg/100m2
# Agricultural Lime (as per soil test)
# Trace elements
# Sterilised poultry manure at 50 kg/100m2
f. Seeded with Penn A1 creeping bentgrass at 0.5 kg/100m2
g. Irrigation applied as required to ensure there is even germination. At about 90% turf cover the depth of the root system was checked and then the irrigation regime gradually reduced by 50%.
h. Mowing height was 3 – 3.5 mm as per typical putting green.

2.8 Establishment
Following seeding the trial was assessed for;
a. Time to germination/seedling emergence.
b. Weekly assessments for % ground cover.
c. Time to achieve 90% turf cover

2.9 Assessments
Once 90 – 100 % turf cover was achieved the trial was assessed for;
a. Visual turfgrass quality: Measured on 16 occasions using a 0-9 rating scale, whereby;
0 = No turf cover, poor quality,
4.5 = 50% grass coverage, average quality,
9 = 100% turf cover, high quality
b. Visual turfgrass density: Measured monthly using a 0-9 rating scale, whereby;
0 = No turf cover, poor turfgrass density,
4.5 = 50% grass coverage, average turfgrass density,
9 = 100% turf cover, excellent turfgrass density
c. Visual turfgrass colour (monthly)
d. Localised dry patch: Presence/absence of localised dry patch was measured as required using a 0-9 rating scale whereby;
0 = No dry spots, high turfgrass quality,
4.5 = 50% of plot affected by dry patch,
9 = Entire plot affected by dry patch
e. Incidence of pests and disease (as required)
f. Root depth: Measured on the 19/9/09, 21/12/09, 9/2/10 and 28/4/10.Samples were taken using a 100 mm diameter hole cutter to a depth of 200 mm. The maximum root depth was measured by measuring the length of the longest root. The depth of the main root mass was also measured by determining the length of the main concentration of roots (refer figure 6).
g. Volumetric water content: Measured using a TDR soil moisture probe (measures volumetric water content). Volumetric water content was measured monthly as well as during a series of dry down studies. There were two dry down studies to determine the moisture retention over time as the profile dried out. The profile was initially watered to achieve field capacity and then the volumetric water content measured over the next 4 days as the profile dried.

3. RESULTS
3.1 Establishment
All plots were seeded using Penn A1 creeping bentgrass at a rate of 0.5 kg/100m2 on February 20, 2009. Plots were visually assessed on a weekly basis after seeding to determine seedling emergence and percent turf cover. The establishment data is detailed in appendix C, table 1. All data has been statistically anaylsed using a one way factor ANOVA (analysis of variance) with a 95% confidence level and the following comments are made;
3.1.1 Seedling emergence
Visual assessments of all plots were conducted 7 days after seeding with no signs of seedling emergence observed. At 12 days after seeding, seedling emergence across all treatments was observed and there was no significant difference between treatments.
3.1.2 Percent ground cover
Percent grass cover was assessed weekly and there was no significant difference in the time taken to achieve a complete turf cove (refer to appendix C, table 1). Figure 1 demonstrates that the Sanoplant™ treatments incorporated at a rate of 1.5 kg/m3 and 3 kg/m3 had a 25% and 22% cover respectively after 28 days compared to the peatmoss and control plots which each recorded a 12% cover, however, statistically there was no significant difference. Figure 1 also indicates that the Sanoplant™ treatment incorporated at a rate of 1.5 kg/m3 was the first to reach a 50% turf cover with a 55% turf cover recorded after 49 days compared to a 35% cover for the Sanoplant™ at 3 kg/m3 and peatmoss treatments and 38% turf cover for the unamended control.

3.1.3 Time to achieve 90% turf cover
At 82 days after seeding, all treatments averaged greater than 80% turf cover with all treatments averaging in excess of 95% turf cover at 100 days after seeding.



3.2 Visual Turfgrass Quality
Visual turfgrass quality assessments were carried out on 16 occasions with turfgrass quality data detailed in appendix C, table 2.

Figure 2 highlights that the overall turfgrass quality of the treatments was variable. The visual turfgrass quality rating for all treatments peaked in December 2009 after full cover was established and before any dry down studies commenced. Following the first dry down study the visual turfgrass quality decreased and there was an increased incidence of localised dry patch. The only significant difference was recorded on the 19-03-10 when the peatmoss treatment was rated as having significantly greater visual turfgrass quality than the remaining three treatments.


3.3 Visual turfgrass density
Turfgrass density assessments were carried out on a monthly basis with turfgrass density data detailed in appendix C, table 3. No significant difference was recorded on any of the assessment dates, however, similarly to the visual turfgrass quality rating, visual turfgrass density for all treatments peaked in December 2009 after full cover was established and before any dry down studies commenced. As with visual turfgrass quality, visual turfgrass density for all treatments was adversely impacted when the application of irrigation was reduced from January 2010 onwards.

3.4 Visual turfgrass colour
Visual turfgrass colour assessments were carried out on a monthly basis with no significant difference being recorded between treatments.
3.5 Localised dry patch
Once a complete turf cover was achieved, a key objective of the trial was to assess the occurrence of dry patch across the treatments when the quantity of irrigation water applied was reduced by 50%.

While no significant difference was recorded between treatments, (refer to Appendix C, table 4) figure 4 demonstrates that the incidence of localised dry patch across all treatments had an adverse impact on all plots from January 2010 onwards, coinciding with the reduction of applied irrigation.



3.6 Incidence of Pests and Disease
The only sign of disease activity affecting the plots was recorded on the 18-09-09 when the fungal pathogen Drechslera spp. was identified. The severity of the outbreak was minor and it was not considered as having a detrimental impact on the overall turfgrass quality and or density. No insect pests were detected impacting the trial throughout the assessment period.

3.7 Root Depth
The depth of the root mass and the maximum root depth were measured across all treatments using a ‘Paraide’ holecutter on four separate occasions. All data was statistically anaylsed using a one way factor anova (analysis of variance) with a 95% confidence level. The data for the depth of the main root mass is detailed in appendix C, table 5 and there was no significant difference recorded over the first three assessment dates. At the April assessment there was a significant difference in the depth of the main root mass, with both Sanoplant™ treatments and the unamended control recording significantly greater root depths than the peat moss treatment.



There was no significant difference for maximum root depth between the treatments recorded over the four assessment dates.



3.8 Moisture Retention
A Fieldscout™ TDR 300 moisture sensor was used to measure moisture retention with volumetric water content (v/v %) data detailed in appendix C, table 7. Figure 8 highlights the assessments conducted outside of the two dry down assessments and recorded a significant difference between treatments on seven separate occasions (18/05/09, 18/09/09, 6/11/09, 2/12/09, 18/12/09, 2/03/10 and 19/03/10) with Sanoplant™ incorporated at a rate of 1.5 kg/m3 consistently retaining greater moisture than the remaining treatments on these dates.



3.8.1 Dry Down Studies
Initially four dry down studies were to be conducted, however due to the high incidence of localised dry patch and associated turf damage recorded from January 2010 onwards, only two studies were conducted.



The first dry down study was undertaken in November 2009 with volumetric water content assessments conducted on the 10/11/09, 11/11/09 and 13/11/09. The only significant difference recorded was on the 10/11/09 when the treatment with Sanoplant™ incorporated at a rate of 1.5 kg/m3 retaining significantly greater moisture than the Sanoplant™ treatment incorporated at a rate of 3 kg/m3 and the peatmoss treatment.

On the morning of the 13/11/09 it was decided to lightly irrigate all treatments to limit the impact of dry patch. Soil moisture assessments were carried out in the afternoon and as figure 9 highlights volumetric water content levels are slightly higher on the 13/11/09 compared to the 11/11/09.

The second dry down study was undertaken in May 2010 with assessments of all treatments being conducted across five dates being the 11/05/09, 13/05/09, 14/05/09, 17/05/09 and 19/05/09. No irrigation was applied during this period, however rainfall increased soil moisture levels before dropping to a low on 17/05/09. The only significant difference was recorded on the last assessment date of the 19/05/09 with the Sanoplant™ treatment incorporated at a rate of 1.5 kg/m3 retaining significantly greater moisture than all other treatments.


4. CONCLUSIONS
A large amount of data has been collected over the trial period with the purpose being to evaluate the effects of incorporation of Sanoplant™ into a sand profile.

“In relation to moisture retention the treatment with Sanoplant™ incorporated at a rate of 1.5 kg/m3 consistently demonstrated throughout the duration of the trial that it retained greater moisture than all other treatments……..”

“In relation to the depth of the main root mass, the April assessment demonstrated a significant difference with both Sanoplant™ treatments and the unamended control recording significantly greater root depths than the peat moss treatment.”

No significant difference was found between treatments when measuring seedling emergence, percent ground cover, turfgrass quality, turfgrass density, or incidence of localised dry patch.


Download the full EVALUATION OF SANOPLANT SOIL AMENDMENT with full tables.

CHISHOLM INSTITUTE OF TAFE, ROSEBUD 2010
Report Prepared By:
John Geary (Environmental Agronomist, AGCSATech)
John Neylan (General Manager)
Andrew Peart (Senior Agronomist)




Learn more about Sanoplant at www.sanoway.com.au or contact the office direct on 07 5580 8787

Read more articles in Consultancy, by John Robertson or from July 2010.