Monitoring Period
Beginning in early to mid-February 2018, Radford University's Field Biology & Phenology class collected observations on plant development along a paved bike path and natural wooded area in Virginia's mountains. Data was recorded based on phenological phases from National Phenology Notebook (NPN, 2018) and submitted to Nature's Notebook on a weekly basis. Target Species Four target species of trees and shrubs were identified to compare phenology (timing of leaf emergence and other phenophases) among native and invasive species in southwestern Virginia. Invasive shrubs: Native trees & shrubs: The characteristics and phenological changes were monitored to document seasonal changes in these species. |
Study Sites |
Data collection sheets were provided by the National Phenology Network's online monitoring database, Nature's Notebook. Monitoring categories were divided into: leaves, flowers, and fruits. Each section is then divided into subsections, and given numeric or percent values for easy tracking.
Leaves: Branches were first searched for breaking leaf buds, which is classified as a green leaf tip which is visible on the end of the bud, but before the first leaf has unfolded. After a breaking leaf bud is found, an estimated number is given for the number of breaking buds (e.g. less than 3; 3 to 10; 11 to 100; etc…). Once unfolded leaves are visible, their canopy space percentage is gauged (e.g. less than 5%; 5%-24%; 25%-49%; etc...), along with percentage of increasing leaf size and percentage of colored leaves. Flowers: We searched first for flower buds that swell and expand throughout the branch. As with breaking leaf buds, the numeric value range is estimated. Then, when flowers or flower buds open and their reproductive parts are visible, they are then classified as “open flowers”, and the percent of open flowers is estimated. Pollen release is recorded when one or more of the flowers on the plant release pollen grains when lightly shaken, and recorded as little or few grains released, some or many grains released, and lots or a layer of pollen is seen when shaken. Fruits: Later in a plant’s development comes fruits. The shape and size is different for every plant, but differentiating between flower and fruit is relatively easy. When a fruit does emerge, they must be counted using the same numerical range, and ripe fruits are given an estimation percentage. Then during the last stages of development, plants will begin dropping their fruits and/or seeds, which is estimated using the numerical range. |
For each given tree or shrub date, time, temperature and humidity of inspection were recorded weekly. We also noted soil moisture of the surrounding area of each tree and shrub (gauged from dry, moist, to wet) and current weather conditions (e.g. rain, snow, etc…). Each tree and shrub were then given a metal tag with their ID (e.g. boxelder-1) and pink flagging to keep track of location. |