DOI: 10.15482/usda.adc/30753383.v1
title: Tall Fescue and Orchardgrass Growth in Beltsville Maryland

description: The goal of this project was to document grass growth so that Maryland NRCS employees would have more accurate information to share with producers growing pastures or hayfields on how much grass they might expect their fields to produce throughout the growing season. This helps the producers better plan for their animals to pasture on the land, so that their grasses, their animals, and their farm businesses all stay healthy.We collected this dataset on grass growth of ‘MaxxQ’ tall fescue and ‘Persist’ orchardgrass over 3 growing seasons, from 2022-2024 at the Norman A. Berg National Plant Materials Center at 8791 Beaver Dam Road in Beltsville, MD, USA. The site is classified at USDA plant hardiness zone 7b, with average monthly temperatures for (2006-2020) ranging from 78° F in July to 34° F in January, and a total average annual precipitation of 44.55 in. The tall fescue was planted into a soil classified as a Russett-Christiana sandy loam soil, 2-5% slope, somewhat excessively drained. This pasture was amended with 50 lb/A Nitrogen and 87 lb/A Potash (K₂O). The orchardgrass was planted into a soil classified as a Fallsington sandy loam with a high water table. This pasture was amended with 3 tons/A lime, and 50 lb/A Nitrogen. To establish the plantings, the fields were treated with glyphosate and tilled. Then the plants were broadcast seeded in August 2020 at the rates of 12 lb/A (orchardgrass), and 6 lb/A (tall fescue). In 2021, the fields were regularly irrigated and mowed, and herbicide was applied as necessary for full stand establishment. From 2022-2024, Nitrogen fertilizer was applied 4 times per year, at greenup (60-80 lb/A), after the first harvest (50-60 lb/A), in late summer (50-60 lb/A) and in late autumn (40-50 lb/A).To collect the biomass data, we used an RCI plot forage harvester (adjusted to clip the grass to 4” high) to clip and collect the 36” wide x 20’ long grass rows. Gross field plot weights and the grasses’ phenological growth stage descriptions were recorded at each clipping. From each plot, one field sample (between 600 – 1000 grams) was collected directly after harvest, placed into labeled cloth bags, weighed (to .1 gram), and dried in a forced air-drying oven. Field samples were dried at between 131° - 140° F for 48 hours for dry matter measurements.For each year, the clippings were started at greenup that season. For orchardgrass data were collected from 4/7/-9/2 in 2022, from 4/6-10/24 in 2023, and from 4/9-10/24 in 2024. For fescue, data were collected from 3/31 to 12/16 in 2022, from 4/6 to 12/13 in 2023, and from 4/9 to 12/5 in 2024. Data was collected at intervals from 7 days to 45 days depending on grass growth rate.Each year, we simulated 3 harvests, since that is a standard management practice. For orchardgrass, these dates were, June 2<sup>nd</sup>, July 22, and September 2<sup>nd</sup>, 2022; May 11<sup>th</sup>, July 26<sup>th</sup>, and October 24<sup>th</sup>, 2023, and; May 14<sup>th</sup>, July 1<sup>st</sup>, and October 24<sup>th</sup>, 2024. For fescue, these dates were June 2<sup>nd</sup>, July 26<sup>th</sup>, and December 8<sup>th</sup>, 2022; May 11<sup>th</sup>, August 3<sup>rd</sup>, and November 30th, 2023, and; May 14<sup>th</sup>, June 1<sup>st</sup>, and December 5<sup>th</sup>, 2024.One forage nutrition sample was collected from each replicate at the conclusion of each phenological growth stage for both grasses in 2024 (4/9, 4/23/5/14, 8/26), dried and submitted for analysis by Waypoint Analytical. These provided measurements of ADF (acid detergent fiber, which measures the digestible portions of the plant), NDF (neutral detergent fiber, which measures the proportion of cell wall in plant tissue, an important factor in food quality for ruminants), protein, TDN (total digestible nutrients), DMI (dry matter intake), and RFQ (relative forage quality, an index value calculated as follows: RFQ = (DMI, as % of body weight) x (TDN, as % of dry matter) ÷ 1.23.