Welcome to Ariadne's Forest Glossary
Glossary: R is for ... radicle, rain, and rootlet.
by Ariadne Unst
Glossary of R...
Forest and Tree Home
Environmental Ethics Blog
- r-selection (n.)
- Natural selection in situations that favor a high reproductive rate (r).
This results in a species that survives by producing many young with minimal
(or zero) individual resource investment by the parents; eggs or newborns are
often abandoned. (r-selected, adj.)
- raceme (n.)
- An inflorescence
where the flowers are arranged singly on distinct but similar unbranched
- radicle (n.)
- Embryonic root.
- ramose (adj.)
- Branched; branchy.
- randomization (n.)
- Randomization (in scientific experiments)
provides data observations that are independently
distributed, as required for the valid application of statistical methods.
By random allocation of experimental units
and the sequence in which trials are conducted: (1) effects of extraneous
factors are averaged out; (2) experimenter bias is removed.
The use of controls
can help varify randomization.
- rain forest (n.)
- The tropical rain forest is a girdle of evergreen forest that
encircles the Earth between the tropics.
- Temperature needs to exceed 21ºC and not exceed 36ºC.
- Moisture of at least 150 cm is required, distributed evenly through the
- Species variety is unusually high: more than 25 species of tree over 30 cm
in diameter grow in a single hectare.
Temperate forests have far fewer. Even in the rich temperate forests of USA's
Appalachia, it is rare to find 12 in a similar area.
- The largest continuous rainforest is in tropical America, centered on the
- Not the same as jungle.
- rare (adj.)
- A species that is uncommon.
Locally Rare: A species that is found in
only a few places within a particular region. It is often more common
- rhizome (n.)
- An underground rootlike stem that is able to producing new roots from its base and
new leaves or stems from its upper surface.
- R horizon (n.)
- The soil horizon below
the C horizon.
- root (n.)
- Large subterranean structure of a plant that provides anchorage. Roots
uptake most of the water and nutrients for the plant.
- root hair (n.)
- Elongated cells, erect on the surface of a small rootlet,
shortly behind the growing tip.
- rootlet (n.)
- Small side branch from a root.
- rosette (n.)
- A cluster of leaves arranged in a circule at the
base of a plant; also called the basal rosette.
Forest and Tree Home,