DOI: 10.5061/dryad.mcvdnck7g
title: Yield development and nutrient offtake in contrasting Miscanthus genotypes under green and brown harvest regimes

description: Harvest time is an important variable that determines the yield of
 miscanthus biomass, its possible end uses, and the nutrient offtake from
 the field. Green harvests result in a higher yield and greater nutrient
 removal from the field. Brown miscanthus harvests, carried out in late
 winter or early spring, result in lower yields, and a lower nutrient
 offtake, whereby the harvested biomass is better suited to use in
 combustion. To look at the long term impact of green harvests on
 miscanthus this experiment followed the yield development of two
 miscanthus genotypes subjected to green and brown harvests over a period
 of seven years at one site in Southern Germany. The standard commercial
 genotype Miscanthus x giganteus (Mxg) was compared to a novel
 late-ripening Miscanthus sinensis genotype: Syn55.  Average
 yields of Mxg were 19.9 t ha-1 for green harvests and 13.2 t ha-1 for
 brown harvests compared to 13.9 t ha-1 and 12.9 t ha-1 for green and brown
 harvested Syn55 respectively. Yields of Mxg were very different for green
 and brown harvests; green harvested Mxg had very high nutrient offtake,
 while brown harvested Mxg had the lowest nutrient offtakes of all
 treatments. Syn55 showed a less marked difference between green and brown
 harvests likely due to its tendency to retain its leaves over winter.
 Syn55 was however not tolerant of a green harvest, with yields of brown
 harvested stands surpassing the yield of green harvested stands in several
 years. Mxg was shown to be tolerant of green harvests, producing
 consistently high yields when harvested in October. Early signs of yield
 decline were detected in both genotypes when harvested green, likely due
 to incomplete carbohydrate relocation. Alternating green and brown
 harvests are recommended to allow stands to replenish carbohydrate stores
 and to form a litter layer.  
description: Harvest data was collected by harvesting miscanthus plants by
 hand and with a field harvester. Samples were taken and dried in a drying
 cupboard to a constant weight. The mineral content of miscanthus biomass
 was determined in the lab following methods laid out by VDLUFA. Mineral
 content data was combined with harvest data to calculate mineral offtake
 in the biomass. <br><br>Temperature data was collected from
 weather stations located at Unterer Lindenhof, operated by the
 Agricultural Technology Centre (LTZ Augustenberg).<br>Temperature
 data were also collected by soil sensors from the company TOMST set up in
 individual experimental plots.<br><br>The McVicker equation
 was used to calculate degree days in the field.
description: # Yield development and nutrient offtake in contrasting Miscanthus
 genotypes under green and brown harvest regimes  The following data has
 been uploaded: Summarised Yield and Offtake Data- this data set contains
 yield data, mineral content data, and mineral offtake data from 2016-2022.
 FM yield and DM yield are in tonnes per hectare. N,P,K,Ca and Mg content
 are in mg per gram. N,P,K,Ca,Mg offtake are in kg per hectare. Weather
 data Unterer Linenhof- this contains weather data from 2016-2023 at the
 experimental site. Soil sensor data- This data set contains data collected
 from soil sensors. Soil temperature is at -6cm beneath the soil surface
 and air temperature is +15cm above the soil surface. Plots 91 and 94 are
 in brown harvested plots Plots 92 and 93 are in green harvested plots.
 Serial cut data contains mineral content data and the fresh and dry weight
 of serial cuts. weight is in grams. SW is the sum of leaf and stem mass
 for one plot. Mineral content is in mg per gram Soil Auswertung contains
 soil data. For nitrogen measurements are in kg/ha for Potassium and
 Phosphorus they are in mg per 100g soil. Missing data code- NA