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Clarifying usage of grades and standards
Dr. Ed Gilman, professor, Environmental Horticulture Department, University of Florida, Gainesville
Florida Grades and Standards for Nursery Stock was designed to improve quality of plant material reaching job sites. Although quality has been increased substantially, there have been reports of misapplications and non-uniform applications of the standards. This has lead to confusion and frustration by growers, contractors, and inspectors. Listed below are some of the more common issues that occur in practice along with an explanation of how the Grades and Standards document addresses that issue.
1) Frustrating issue: Only shade trees with straight leaders are allowed, a dominant leader is not enough.
What grades and standards says: The document says on page 3 that "Live oak and some other trees can have a modified dominant leader as shown in Figure 1 on page 10." Page 10 goes on to say for Florida Fancy "There is one trunk, more or less in the center of the tree as shown above. Some trees such as Chinese elm, live oak, royal poinciana, Jerusalem thorn, mahogany and some others can be grown with a modified (not straight) trunk as shown." The Grades and Standards update available here trunk divides in two nearly equal-diameter stems in the upper 10% of the tree, the trunk is not downgraded to a Florida #1."
The
document says for Florida #1: "The trunk branches (forks) into two nearly
equal-diameter trunks in the upper 1/2 of the tree. (If one trunk is 2/3 or
less than the diameter of the other trunk, they do not have equal diameters,
making the trunk Florida Fancy.) A noticeable but small void will be left in
the crown after removing the top portion of one of the trunks. If there is one
trunk, but it has a 5 to 15 degree bow, grade it Florida #1." In other
words the document allows up to a 15 degree bow for a Florida #1.
Summary statement: The grades and standards document says that shade trees do not have to have straight trunks in order to meet Florida #1 grade. It says that a dominant leader is enough. If a buyer wants the trunk to be straight then state that in the plant specifications for nursery stock. The word "straight" should be defined very specifically because the Grades and Standards document does not define straight since it is not part of the grading process. The document allows for subordinating (pruning) one of the two codominant stems in the top half of the tree.
2) Frustrating issue: No significant branches are allowed in the lower 10' of the trunk.
What
grades and standards says: The document says on page 11 for Florida Fancy
and for Florida #1 that "No branches are greater than 2/3 the diameter
of the trunk measured directly above the branch."
Summary statement: The grades and standards document says that shade trees can have branches up to 2/3 the trunk diameter any place on the tree without those branches being considered trunks. If those branches are greater than 2/3 the trunk diameter then they are considered trunks and the tree is graded accordingly. If buyers want branches in the lower portion of the tree of a certain diameter, then they should specify that in the bid document. However, since keeping branches less than a specified diameter is not a grades and standards issue (other than keeping them less than 2/3 trunk diameter), it might be challenging to find tree growers producing trees with these specifications.
3) Frustrating issue: Trees are rejected even after circling roots are cut at the point of circling
What
grades and standards says: The document says on page 5 "Circling roots
less than 1/3 the trunk diameter can be cut at the point where they begin to
circle. Following cutting, the tree is no longer a Cull."
Summary statement: The document says that when circling roots less than 1/3 the trunk diameter are cut the tree is no longer a Cull due to the circling root. The document does not address the issue of more than one circling root needing to be cut.
4) Frustrating issue: Trunks must be completely clean and scar-free for at least the first 4' from the ground up. No marks are allowed in the first 4' of trunk.
What
grades and standards says: The trunk injury issue is addressed on page 5
in Step 9c of the Grades and Standards. It takes two true statements in Step
9 to downgrade the tree to a lower grade. Therefore if there is an injury on
the trunk, and that is the only true statement in Step 9, then a Florida #1
tree is not downgraded. But there is more: Step 9c also states that "(Open
trunk wounds must be less than 10% of the trunk circumference and less than
2 inches tall on Florida #1 trees. An open pruning scar on the trunk resulting
from removing a branch is not considered an open trunk wound.)"
Summary statement: If your wound is smaller than 10% of the trunk circumference and the wound is less than 2 inches tall then a Florida #1 tree is not downgraded. However, since it takes only one true statement in Step 9 to downgrade a Florida Fancy, a tree with this wound would be downgraded to a Florida #1. If the wound is larger than 10% of the circumference or more than 2 inches tall then the tree is downgraded.
5) Frustrating issue: No open (sometimes referred to as unhealed) cuts are allowed where branches were subordinated (reduced in length) anywhere on the tree.
What
grades and standards says: The document refers to subordination pruning
in one sentence on page 10 in the Florida #1 text on the bottom left portion
of the page. It says "A noticeable but small void will be left in the crown
after removing the top portion of one of the trunks."
Summary statement: This statement in the document encourages professionals to subordinate (reduce the length of) one of the stems if there are two codominant stems. This is a recognized, appropriate arboricultural procedure in practice today. It is not essential for this pruning wound to be closed before the tree is planted in the landscape. Step 9c on page5 of the document refers to trunk wounds only, not other pruning wounds on the tree.
6) Frustrating issue: No branch subordination is allowed on the job site (trees are rejected that would pass with minor subordination), yet the inspector will not go to the field to demonstrate what they want. It makes it a gamble every time you go onto one of their jobsites.
What
grades and standards says: The document refers to this type of pruning in
one sentence on page 10 in the Florida #1 text on the bottom left portion of
the page. It says "A noticeable but small void will be left in the crown
after removing the top portion of one of the trunks."
Summary statement: This statement in the document encourages professionals to subordinate (reduce the length of) one of the stems if there are two codominant stems. This is a recognized, appropriate arboricultural procedure in practice today. It is not essential for this pruning wound to be closed before the tree is planted in the landscape. The tree could technically be downgraded based on canopy symmetry if the resulting void was large enough. But in the overall long run, this is likely to be a small issue.
7) Frustrating issue: Several inspectors are rejecting trees because the leader was tipped in the nursery to help reestablish the leader.
What
grades and standards says: The document on page 10 is clear on this matter.
In the text describing both Florida Fancy and Florida #1 the document states
"The tip of the leader on the main trunk must be intact and its terminal
bud must be the highest part of the tree." If the leader is not intact
then the tree is a Florida #2.
Summary statement: This statement says that if the tree was headed (also called tipped or topped) recently so there is no clear leader re-established, then the tree is a Florida #2. So if there are no sprouts coming from the cut, of if there are many small short sprouts coming from the cut, then the tree is a Florida #2. However, if the tree received this treatment some time ago and the leader has been re-established, then the tree is not downgraded for this. In other words plenty of trees are tipped or topped in the nursery. For some species this is a common practice that results in a high quality shade tree that meets Grades and Standards.
8) Frustrating issue: Trees planted too deeply in the root ball are rejected.
What
grades and standards says: Nothing at all.
Summary statement: This issue is outside the scope of the document since it is not addressed at all. The Grades and Standards should not be used to reject trees that are planted too deeply in the root ball. You must address this issue in the planting specifications or in some other document because it is not in the Grades and Standards.
9) Frustrating issue: Trees are rejected if they have a dog leg anywhere in the canopy, no matter how high up.
What
grades and standards says: The Grades and Standards document printed in
1998 page 10 in the Florida #2 text on the bottom right portion of the page
states "If there is one trunk, but it has a bow greater than 15 degrees
or a dog leg (see glossary), grade it #2. This created some confusion so this
was clarified in the update. The update published on the Division of Plant Industry
web site (click here for updates) states "A dog leg in the crown of the
tree is not a downgrading factor."
Summary statement: Do not downgrade a tree if it has a dog leg above the point where the canopy begins. In other words if the dog leg is inside the canopy, do not downgrade the tree.
