Plant Density - Robel Pole Method

Materials & Equipment:

Plastic coated, metal pole, 1.8 m long by ~1 cm diameter—available at most garden stores
Time tape, 0.75 inches wide, red and orange
Meter tape
Meter stick
PVC frame, inner dimension 2 meters x 0.5 meters
Clipboard
Field data sheet
Pencil

Method:

Robel Pole Construction: Mark the pole with tape in 10 cm intervals at measurements from 10 to 150 cm, beginning at the bottom of the pole with 10 cm from the tip. Align the tape so the top edge of the tape is at the 10 cm incremental mark. Use orange tape for 50, 100, and 150 cm; use red tape for the other markers. Label each tape increment with the distance from the bottom of the pole.

1. Use the long side of the frame to measure two meters north from the plot flag. Position the 0.5 × 2 meter frame with the long side extending north. This is the area that will be harvested for biomass.

2. Position the Robel Pole in the center of the harvest area. Attach the end of the meter tape to the pole and extend the tape to 4 meters from the pole in one of the cardinal directions (north, east, south, or west). Using the meter stick as a guide, the reader observes the pole from an eye-level of 1 m above the ground. The lowest tape mark visible on the pole is recorded.

3. The reading is repeated three more times in the remaining cardinal directions. All four readings are repeated by a second person.