|Plants & Human Affairs (BIOL106) - Stephen G. Saupe, Ph.D.; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321; firstname.lastname@example.org; http://www.employees.csbsju.edu/ssaupe|
Objectives: Upon completion of this lab you should be able to:
Airborne pollen, which is the major cause of hay fever, is shed from wind-pollinated plants. The flowers of these plants are well adapted for this mode of pollination. Among their characteristics, wind pollinated plants typically:
As a result, wind-pollinated plants have inconspicuous flowers that are often not observed by the casual botanist. Among the common wind-pollinated plants are oaks, birches, maples, pines, grasses, ragweed, sage, pigweed, and lamb's quarters.
The amount of pollen in air can be measured a variety of ways. At the CSB/SJU Center for Pollen Studies we use a Rotorod sampler. This is an impact sampler that has two grease-coated rods that spin around and catch pollen. The pollen grains on the rods are then identified and counted. Based on the area of the rods, the time the rods are left in the field, and the speed at which the rods are spun, we can calculate the pollen per cubic meter of air. In this lab we will analyze a pollen sample collected by the Rotorod sampler. For more information about pollen sampling, check out the CSB/SJU Center for Pollen Studies web site and the links cited, especially articles from Multidata Inc.
Analysis of a Rotorod Pollen Sample.
|pollen count (grains m-3 )||=||
# of grains counted
%Duty Cycle actually used
% of rod actually counted
where: 3.12 m3 = the calculated volume of air Rotorod Sampler measures in standard conditions (1440 minutes, 10% Duty Cycle and 100% of rod counted)
|Table 1. Pollen Sample Collection Data|
|Sample date (if known)|
|Start date (if known)|
|Finish date (if known)|
|Length of count (min)|
|Table 2. Pollen Count for ( insert date)|
|Pollen Observed (tick marks)|
|Pollen Count (grains m-3)|
Last updated: 07/29/2005 / � Copyright by SG Saupe