.. age of associated species, as well as history of disturbance of the site. ...... Postfire colonization and spread: Observations by Caplan [34,35] suggest ...... The biodiversity and distribution of exotic vascular plants and animals ...
www.fs.fed.us/database/feis/plants/tree/elaang/all.html

... vegetation or re-established following disturbance of the site. ...... a. plant species and seeding rates must take into account soil, slope, climate, ...
www.maine.gov/sos/cec/rules/06/096/096c400.doc

... less than 33 percent cover of planted or naturally reestablished herbaceous wetland species within one growing season following disturbance of the site, ...
https://www.flrules.org/gateway/readFile.asp?sid=0&tid...typ...

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Note added at 12 hrs (2010-03-15 13:41:14 GMT)
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Thanks for all that interesting context. I stand by my suggestion. "Disturbed site" and "disturbed soil" are common expressions in agricultural science and horticulture. Note the following examples:

61,000

(3) Native sedges established on the disturbed site in 5-10 yr, producing an above-ground biomass equal to that in undisturbed tundra. ...
www.jstor.org/stable/2402339

Soil-plant Diversity Relationships on a Disturbed Site in Northwestern Colorado1. John M. Stark and Edward F. Redente2. ABSTRACT ...
soil.scijournals.org/cgi/content/abstract/49/4/1028

This observation is especially significant in a disturbed site where seedling establishment would probably be very poor, and spreading by rhizomes or ...
www.co.bell.tx.us/bellnet/bellnetweb/web/DisturbedSite.htm -

Vertical Structure and Abiotics of Disturbed and Undisturbed Site
The purpose of this data report was to compare the vertical structure of two quadrats, one a disturbed site and another an undisturbed site, ...
maine.washcoll.edu › Student Reports

Tree density, basal area and species diversity in a disturbed dry ...
by R SAGAR - Cited by 2 - Related articles
significant only when extremely disturbed site was included in the analysis. ... the data from the most disturbed site (Kota) was excluded from analysis. ...
journals.cambridge.org/production/action/cjoGetFulltext?fulltextid

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Note added at 1 day4 hrs (2010-03-16 06:13:31 GMT)
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The addition text confirms my position. I don't think it could be anything else but 'disturabance of the site'.