We have all, no doubt, observed enlarged or exagerated butress roots on trees growing in wet or swampy conditions. The most notable example is cypress which is a true swamp plant and exhibits this characteristic more frequently than not.

Is the atypical presence of such a characteristic on trees (e.g. Acer rubrum, Ulmus sp.) which are equally or more likely to be found in dry or "upland" environments considered to be a definitive indicator of perennial or seasonal "wetland" soils? Is there literature on this? I'm specifically interested in the legal characterization of "inland wetlands" which in some states is accomplished through soil types and in some states through plant types (both serving as indicators of wetland function).

TIA, Scott.

Reply to post by Scott Cullen, on February 25, 1999 at 07:28:35:

Scott,

I know that in Illinois, a cypress planted on an extremely dry heavy clay site in 1988-89 showed absolutely no damage from the drouth. It was planted with a tree spade many years before at the proper depth, but the trunk enters the ground like a phone pole. There are several on Western Il. Univ. campus like this. Also some growing on edge of a small pond, with the typical buttress and knees. I know from this that cypress exhibits the differences you mention, but have no taken notice of others. This prairie pothole country had ought to be a good place to observe the difference between well drained and waterlogged, just as soon as the 2 - 4 feet of snow melts off.

Amazing how much a plant can tell us about everything in the world, isn't it?

Bob U.

Reply to post by Scott Cullen, on February 25, 1999 at 07:28:35:

The US Army Corps of Engineers publishes "Corps of Engineers Wetland Delineation Manual" in Jan 1987. It further clarified it's procedures in a February 1992 memorandum. NTIS No. AD-A176734

1. Basically 50% of dominant species from all strata (tree, sapling, shrub, herb) must be either "obligative" (definitely wetland) or "facultative" (occurs in both wetland and upland) species (as determined by the official wetland plant species list for the region).

2. Furthermore, if morphological adaptations (buttressing, algae growth, shallow roots, etc.)are observed on two or more species hydrophytic conditions are said to exist. This is used to further clarify conditions.

3. Areas seasonally inundated to the surface for more than 12.5% of the growing season are wetlands. 5% to 12.5% MIGHT be wetlands, and less than 5% are not wetlands.

4. Soil conditions such as oxidized rhizospheres, mottling, SCS soil survey classifications, gleyed soils within 10 inches of the A horizon, hydric soils, and other soil factors are also considered.

That's just the ACOE standard. Furthermore, each state, region, and sometimes county have systems to designate wetlands for their own local jurisdictions. On one project we had four different wetland lines (ACOE, State, County, and river basin). On another, the state line (Florida) covered 12 acres beyond that covered by the ACOE line. On another, the state line covered LESS than the ACOE line.

The State of Florida has since consolidated it's methodology under Chapter 62-340, F.A.C. which is published in "The Florida Wetlands Delineation Manual". Now we have just the two lines to worry about, ACOE and State.

In short, a field determination requires someone with the proper training to review the maps, visit the site, dig holes, and inspect the vegetation, soil color, hydrological evidence, and compare with the local regulations that are in effect on that particular site. This is usually done in conjunction with a threatened and endangered species ("T&E") survey. The line is flagged or staked in the field, verified by agency staff personnel and then surveyed by a licensed surveyor. The information is used to restrict certain types of development on the wetland side of the line. Generally the agency staff persons are very helpful in the process.

Reply to post by Scott Cullen, on February 25, 1999 at 07:28:35:

Paul & Bob,

Great stuff, thanks. I'll get a look at the ACOE stuff and I have a board meeting with the local Dir. of Env. Prot. and I'll ask him about state stuff.

The property in question sits ontop of the state line so we have two potential sets of regs, though I suspect all development will be on one side of the line only. The state regs in both of these states are administered by local Inland Wetlands Commissions who have a lot of autonomy in interpretation and enforcement. In one of the states we may have county level involvement as well. My involvement is on the real estate side not the technical side and we have good engineers fully competent in both states to actually undertake the delineation and mapping. My question was more for my own understanding of how definitive an indicator buttressing might be characterized to be. Thanks for the input.

Reply to post by Scott Cullen, on February 25, 1999 at 07:28:35:

Buttressing is also common in extremely shallow soil conditions, which are in many ways like poorly drained sites. It's as if a tree is saying, "Gotta hold myself up somehow... better buttress."