Ag Data Commons
2 files

Data from: Switchgrass cultivar, yield, and nutrient removal responses to harvest timing

posted on 2024-02-09, 17:43 authored by Amanda AshworthAmanda Ashworth

Finite nutrients, such as P and K are assumedly remobilized post-senescence in herbaceous feedstocks like switchgrass (Panicum virgatum L.) as a function of environmental signaling and genotype. Harvesting early during the maturation phase may result in yield reductions and higher nutrient removal in biomass depending on ecotype. Therefore, it is necessary to target harvest dates that optimize yield while minimizing nutrient removal per cultivar. Consequently, objectives were to compare yields from 2010–2011 on eight widely used and experimental upland and lowland genotype (whole plot) at two locations in Tennessee, to determine: (i) which harvest timing (split-plot) provides maximum yield; (ii) effects of harvest timing (mid-September, October, November, and late October) on overall total P and K removal; and, (iii) how results are affected by cultivar. Among all post-senescence harvests, yields peaked early November (13.2 Mg ha–1), which was greater than all other harvests (P < 0.05), with mid-October and late October not differing from one another. Because yields peaked in early November, P and K removal did not vary across harvest dates (despite both P and K concentrations declining mid-October). Lowland cultivars yielded 3.9 Mg ha–1 more biomass annually than upland entries, suggesting lowland cultivars are better suited to environments in the Southeast. Due to lower yields, P and K removals were lower for upland (Blackwell and C62), compared with lowland cultivars. Consequently, switchgrass can be harvested as early as mid-September without removing greater amounts of P and K, although variations within upland and lowland cultivars will likely occur.

Resources in this dataset:

  • Resource Title: Switchgrass variety nutrient removal.

    File Name: variety removal.csv

    Resource Description: Switchgrass variety P and K tissue (leaves and stems) removal for fall harvest periods (mid-September, October, November, and late October), at East Tennessee and Highland Rim Research and Education Centers from 2010–2011.

  • Resource Title: Data Dictionary.

    File Name: switchgrass-variety-nutrient-removal-data-dictionary.csv

    Resource Description: Defines variables, units, and data types for the tabular data.




Data contact name

Ashworth, Amanda


Ag Data Commons

Intended use

To compare switchgrass yields as related to elevation, harvest timing, total P and K removal, and cultivar.

Temporal Extent Start Date


Temporal Extent End Date



  • Not specified

Geographic Coverage


Geographic location - description


ISO Topic Category

  • biota
  • elevation
  • environment
  • farming

National Agricultural Library Thesaurus terms

nutrients; feedstocks; Panicum virgatum; genotype; biomass; ecotypes; harvest date; cultivars; highlands; Tennessee; phosphorus; harvesting; potassium; biogeochemical cycles; nutrient offtake; plant nutrient resorption; crop yield; forage yield

OMB Bureau Code

  • 005:18 - Agricultural Research Service

OMB Program Code

  • 005:040 - National Research

ARS National Program Number

  • 212

Primary article PubAg Handle

Pending citation

  • No

Public Access Level

  • Public

Preferred dataset citation

Ashworth, Amanda (2019). Data from: Switchgrass cultivar, yield, and nutrient removal responses to harvest timing. Ag Data Commons.