Definition: There is no evidence that the organism produces compounds (allelochemicals) that influence the growth, survival, and reproduction of other organisms.
Definition: The percentage of organic carbon divided by the percentage of total nitrogen in organic material is lower than 23.
Comment: USDA Plants database specifies the organic material as either the above ground biomass of an herbaceous plant or the above ground herbaceous material of a woody plant.
Definition: A color hue with high wavelength of the long-wave end of the visible spectrum, evoked in the human observer by radiant energy with wavelengths of approximately 630 to 750 nanometers.
Definition: A porosity quality inhering in a bearer by virtue of the bearer's being incapable of admitting the passage of gas or liquid through pores or interstices.
Definition: A porosity quality inhering in a bearer by virtue of the bearer's being capable of admitting the passage of gas or liquid through pores or interstices. (or, as in fungi, solids such as spores may be admitted through pores in the hymenium, for example)
Definition: A landform that extends above the surrounding terrain in a limited area. A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill although a mountain usually has an identifiable summit and a local relief of more than 300m.
Definition: An area that is inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.
Definition: An area that is inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.
Definition: A color hue with medium-low wavelength of that portion of the visible spectrum lying between yellow and blue, evoked in the human observer by radiant energy with wavelengths of approximately 490 to 570 nanometers.
Definition: Of plant duration, a plant whose life span ends within one year after germination, e.g. a winter annual germinating in the autumn and flowering in the spring (esp. in Mediterranean climates), approximately synonymous to therophyte, c.f. biennial, ephemeral, perennial, c.f. also of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic.
Definition: Of plant duration, a plant whose life span extends over more than two growing seasons, c.f. annual, biennial, ephemeral, of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic
