ss="section level4">
<h4 id="additional-information-about-trees-through-field-data">Additional information about trees through field data<a class="anchor" aria-label="anchor" href="#additional-information-about-trees-through-field-data"></a>
</h4>
<p>If supplementary field data is available for the sample plots, a data
frame containing this information can be included in
<strong><code>tree.field</code></strong>. Each row of the data frame
must represent a tree and the data frame must contain at least the
fo