| |
| Web URL(s): | https://listings.lib.msu.edu/iowat/1991.pdf#page=61
Last checked: 01/10/2017
Requires: PDF Reader |
|---|
| Publication Type:
| Report |
|---|
| Author(s): | Kassmeyer, S. M.;
Agnew, M. L. |
|---|
| Author Affiliation: | Technical Assistant, Field Research Area; Associate Professor, Extension Turfgrass Specialist, Horticulture Department, Iowa State University |
|---|
| Title: | CORON research at Iowa State University |
|---|
| Source: | 1991 Iowa Turfgrass Research Report. July 1991, p. 56-63. |
|---|
| Publishing Information: | Ames, Iowa: Iowa State University |
|---|
| Keywords: | TIC Keywords: Fertilizers; Foliar burn; Poa pratensis
|
|---|
| Abstract/Contents: | "CORON Burn Study: A foliar burn study was designed to compare the effects of two fertilizer sources, two nitrogen rates, and three water dilution rates on the burn potential of Kentucky bluegrass, Poa pratensis L. The two fertilizer sources were CORON (28-0-0) and urea (46-0-0). The intended nitrogen rates were 1 and 2 lb N/1000ft2 for both N sources. However, due to a calculation error, the nitrogen rate for CORON on the first treatment date was 2 and 4 lb N/1000 ft2. Each fertilizer source and nitrogen rate was diluted into 1-, 3-, and 5-gal of water/1000 ft2. A list of treatments is included on Tables 27, 28 and 29. Each plot measured 5 ft by 5 ft and was replicated 3 times in a randomized complete-block design. Irrigation was provided to the plots to prevent drought stress. All plots were maintained at a cutting height of 2 in prior to treatments. Plots left unmowed for 2 weeks following the initial treatment. Treatments were applied on the following cultivars of Kentucky bluegrass: 'Glade' on June 28, 'Park' on July 16, and 'Glade' on September 5. Burn ratings and recovery quality data were recorded after each treatment. Burn rating was a visual rating of each plot. All ratings were made on a scale of 1 to 9, with 1 = dead turf and 9 = no burn. Recovery quality was a visual rating of each plot. This rating was also based on a scale of 1 to 9, with 1 = straw brown turf, 9 = green turf and 6.0 a minimum acceptable level. The first burn treatment was made in late spring. As stated above, N rates for CORON on the first treatment date were 2 and 4 lb N/1000 ft2. The data shows that 4 lb of N applied as CORON can cause a great deal of burn (Table 27). The CORON treatment at the 2 lb N rate showed less burn than the urea treatment at a 2 lb N rate. The water rate had no effect on burn potential for this application. The recovery rate of the burn plots was exceptional. The CORON treatments containing 4 lb N rates produced a very dark green turf by mid-August. The second burn treatment was made in midsummer. Urea caused immediate burn. The plants quickly outgrew the foliar burn. The common bluegrass cultivars coupled with excessive rains probably helped decrease the burn effect. CORON caused very little burn after this treatment (Table 28). Regardless of N source, the 2 lb N rate caused greater burn, but it had a better recovery than the 1 lb N rate. CORON-treated plots generally recovered better than urea treated plots. While water rate did not affect initial burn, it did affect the recovery rate. Plots treated with the 3 to 5 gal water rate recovered better than plots treated with the 1 gal water rate. The last treatment date was intended for cooler fall weather. However, September was the hottest, driest month in during 1990. Urea-treated plots had a greater burn rate than CORON treatments (Table 29). In addition, urea at the 2 lb N rate had the most severe burn, while CORON at the 2 lb N rate had the best overall rating on the second and third rating date. The 2 lb N rate had the best overall rating on the second and third rating date. The 2 lb N rate recovered better from the burn and the water rates of 3 and 5 gal had better recovery areas. In summary, CORON can cause severe burn if applied at excessively high N rates (4 lb N). However, even at these high rates, the recovery of plants treated by CORON was excellent. In contrast, urea caused severe burn but didn't recover as well as CORON. IN addition, it is best to use a 3 or 5 gal water rate when using urea. CORON Response Study: This study was designed to compare the length of response of 2 N sources (CORON 28-0-0 and Nutriculture 28-8-18) and 3 N rates (0.1, 0.2, 0.3 lb N) on a high sand content green. This study was conducted on a USGA green with a rootzone mixture of 80% sand, 10% peat, and 10% silt. The pH of the green was 8.3; P and K levels were low. Two lbs K20 were applied to the entire green on June 10, 1990. The turfgrass species was (Creeping Bentgrass) Agrostis palustris L. Fertilizer applications were made on June 17, July 27, and August 8. Each fertilizer was applied wdith a 3 gal water/1000 ft2. Each plot measured 5 ft by 5ft and was replicated 3 times in a randomized, complete-block design. The plots were maintained at a 1/4 in mowing height and irrigated as needed. Visual quality ratings were taken after each treatment application, until there were no visible treatment effects. Ratings were made on a scale of 1 to 9 with 1 = to dead, straw brown turf and 9 = dark green dense turf. Figures 3, 4, and 5 show that CORON applied at 0.3 and 0.2 lb N rates produced the est quality turf in this study. While CORON treatments produced higher ratings than the Nutriculture treatments, all treatments will produce an acceptable quality turf. The 0.1lb N rate of Nutriculture showed less then unacceptable quality rating only twice in this study. In summary, CORON provided a better quality turf than Nutriculture. The CORON provided better efficacy because it is most likely not as mobile as the Nutriculture." |
|---|
| Language: | English |
|---|
| References: | 0 |
|---|
| Note: | Article appears as abstract
Tables |
|---|
| ASA/CSSA/SSSA Citation (Crop Science-Like - may be incomplete):
Kassmeyer, S. M., and M. L. Agnew. 1991. CORON research at Iowa State University. Iowa Turfgrass Res. Rep. p. 56-63. |
| Fastlink to access this record outside TGIF: https://tic.msu.edu/tgif/flink?recno=29308 |
| If there are problems with this record, send us feedback about record 29308. |
| Choices for finding the above item: |
|---|
| Web URL(s):
https://listings.lib.msu.edu/iowat/1991.pdf#page=61
Last checked: 01/10/2017
Requires: PDF Reader |
| 
MSU catalog number: SB 433 .A1 I55 |
| Request through your local library's inter-library loan service (bring or send a copy of this TGIF record) |
