6 TREE ATTRIBUTES FOR WILDLIFE

Contents

Tree Attributes for Wildlife Form
Field Procedure
Selecting the Sampling Method
Selecting the Minimum Diameter
Selecting a Basal Area Factor Prism
Selecting the Plot Size and Shape
Completing the Form
1.	Project Identification
2.	Date
3.	Surveyor
4.	Plot Number
5.	Basal Area Factor
6.	Plot Size
7.	Minimum Diameter
8.	Species
9.	Standing/Fallen
10.	Diameter at Breast Height
11.	Measured or Estimated
12.	Remaining Bark
13.	Length
	Slope to top of tree
	Slope to DBH or bottom of tree
	Bottom position
	Slope distance
14.	Estimated Length
15.	Crown Class
16.	Height to Live Crown
17.	Wildlife Codes
	Appearance
	Crown condition
	Bark retention
	Wood condition
	Lichen loading
	Wildlife use
Appendix
6.1	Tree species codes
Tables
6.1	Crown condition codes
6.2	Bark retention codes
6.3	Wood retention codes
Figures
6.1	Visual appearance codes for wildlife trees

Tree Attributes for Wildlife Form

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Field Procedure

Getting Started

1.	Identify sample trees based on a prism sweep, or if using a fixed-area plot, establish plot boundaries. Be aware of the minimum DBH for the project.
2.	If desired, tag or flag numbers on each tree including all live and dead, standing and fallen trees.

Measure and Record

1.	Enter the header information.
2.	For each sample tree, record the species and classify as standing or fallen.
3.	Determine DBH and percentage of bark remaining at breast height.
4.	Record data required to calculate the length of each sample tree, or estimate length.
5.	For each standing live tree, assign a crown class and determine height to live crown.
6.	For each sample tree, assess appearance, crown condition, bark retention, wood condition, lichen loading, and wildlife use.
7.	Check that all the required information has been collected and noted on the form. Strike through any fields that were not assessed.

Selecting the Sampling Method

Either a fixed-area or variable-radius plot may be used. Variable-radius plots will be used most commonly, but if the project area is dominated by stands with the following characteristics, a fixed-area plot may be preferable:

very open stands with widely spaced trees or clumps of trees
very dense stands where not all trees in a plot would be easily visible

Once selected, the same plot-type should be used consistently throughout the project.

Selecting the Minimum Diameter

The minimum diameter at breast height (DBH) is determined by the wildlife species of concern in the projectthe goal is to sample a reasonable number of trees of an appropriate minimum size for the species. For example, for Bald Eagle interpretations, trees less than 20 cm DBH are not of value and may be ignored. For most projects, the minimum DBH will be 15 cm or greater. Trees less than the minimum DBH are ignored

Selecting a Basal Area Factor Prism

The basal area factor (BAF) prism size should be based on previous experience. A prism size that will provide 7-11 sample trees (greater than or equal to the minimum DBH) per plot is ideal. A minimum of 5 and maximum of 16 trees is required. Generally, the larger the trees, the larger the BAF; the denser the stand, the smaller the BAF required. It may be necessary to have several prisms available throughout a project. When traversing the stand, but before determining the plot location, the prism size should be selected.

Selecting the Plot Size and Shape

For fixed-area plot sampling, a plot size is selected that will provide ten or more sample trees greater than or equal to the minimum DBH. The plot size is determined for a project and is only reduced or increased in exceptional circumstances. The decision of whether to increase or decease, e.g., double or halve, the plot size is done when entering the stand, before the plot is marked, so as to minimize bias.

Plot shape can be circular, square, or rectangular, but should be determined at the start of a project.

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