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Methods for Experiment 116 -

Experiment layout and treatments

In 1993, 50 4x8m plots were set up in Field C, adjacent to e001 and other experiments. Field C was abandoned from agriculture in 1934 and had reverted to mixed grassland. Twelve experimental treatments were applied to plots in a completely randomized design. Functional groups were designated as C3 grasses, C4 grasses and forbs and were selectively removed from plots to create all possible combination of 1, 2 or 3 functional groups remaining. Two additional treatments were created by randomly removing either 25% or 55% of the vegetation in a plot and three more treatments were created by planting Poa pratensis, Solidago rigida, or Schizachyrium scoparium in monocultures. Each treatment had 4 replicates, with the control (no plants removed) having 6 replicates. Plants were initially removed by killing them either by hand-painting leaves with a non-selective herbicide (Roundup, Monsanto), or by spraying with a selective herbicide (AMINE 4-Platte Chemical Co.-for forbs, Poast Plus-BASF Corp to remove graminoids). All of these herbicides should be non-toxic to insects. Some herbicide was used again in early 1994, but thereafter treatments were maintained by hand weeding from elevated platforms. Plots were burned in May, 1994.

abve116 - Arthropod D-Vac Sampling

Arthropod D-Vac Sampling

Arthropod sampling took place on 30 June, 26 July and 4 September, 1995. Eight D-Vac samples of 20cm diameter each were taken with a Vortis ? insect vacuum sampler (airflow 10L/s) in the central 2x6 meters of each plot. Forty-two of the 50 plots are presented in this dataset. Samples were frozen, and then sorted under a microscope, primarily by John Haarstad. All arthropod specimens were identified to species or morphospecies within known genus or family and enumerated. Each taxonomic division was assigned a general and specific trophic feeding category. *Note about comparing experiments: morphological notes may not indicate the same species/group in different experiments.

Arthropod D-Vac Sampling: Data Preparation

Data preparation was done by Amy Symstad and John Haarstad. Colleen Satyshur translated arthropod codes to full taxonomic descriptions based on files from Amy Symstad, Evan Siemann and paper files in Haarstad?s records.

Table of e116 plot treatments, noting which are present in Arthropod D-Vac Sampling data set.

TreatmentPlot NumberIn.DatasetForb.presentC3.presentC4.present#Funct.Groups
Forbs removed13yes0112
Forbs removed27yes0112
Forbs removed30yes0112
Forbs removed38yes0112
C3 graminoids removed2yes1012
C3 graminoids removed14yes1012
C3 graminoids removed39yes1012
C3 graminoids removed42yes1012
C4 graminoids removed3yes1102
C4 graminoids removed37yes1102
C4 graminoids removed41yes1102
C4 graminoids removed44yes1102
Forbs & C3 graminoids removed23yes0011
Forbs & C3 graminoids removed28yes0011
Forbs & C3 graminoids removed33yes0011
Forbs & C3 graminoids removed43yes0011
Forbs & C4 graminoids removed5yes0101
Forbs & C4 graminoids removed8yes0101
Forbs & C4 graminoids removed10yes0101
Forbs & C4 graminoids removed24yes0101
All (C3 & C4) graminoids removed11yes1001
All (C3 & C4) graminoids removed47yes1001
All (C3 & C4) graminoids removed48yes1001
All (C3 & C4) graminoids removed51yes1001
25% random biomass removed9no1113
25% random biomass removed19no1113
25% random biomass removed31no1113
25% random biomass removed50no1113
55% random biomass removed25no1113
55% random biomass removed26no1113
55% random biomass removed32no1113
55% random biomass removed46no1113
Schizachyrium scoparium monoculture (planted)7yes0011
Schizachyrium scoparium monoculture (planted)34yes0011
Schizachyrium scoparium monoculture (planted)40yes0011
Schizachyrium scoparium monoculture (planted)45yes0011
Poa pratensis monoculture (planted)16yes0101
Poa pratensis monoculture (planted)20yes0101
Poa pratensis monoculture (planted)21yes0101
Poa pratensis monoculture (planted)36yes0101
Solidago rigida monoculture (planted)1yes1001
Solidago rigida monoculture (planted)12yes1001
Solidago rigida monoculture (planted)18yes1001
Solidago rigida monoculture (planted)35yes1001
Control (no treatment)6yes1113
Control (no treatment)15yes1113
Control (no treatment)17yes1113
Control (no treatment)22yes1113
Control (no treatment)29yes1113
Control (no treatment)49yes1113