An indicator plant is a usually weedy plant that grows in some specific environment, allowing an assessment of soil and other conditions in a place by simple observation of vegetation. Dandelions, shown here in proliferation, are commonly thought of as weeds. ... For the heavy metal band see Soil (band) Soil is unconsolidated rock particle that lies on the surface of the earth, intermingled, perhaps, with organic matter from plant decay. ...

Much useful knowledge can be obtained about our land by observation of the wild plants and cover crops that are growing, and their condition. These include indicating fertility levels and potential nutrient deficiencies, waterlogging or compaction problems, pH levels and so on. When assessing land by observation of indicator species however it is good practice to observe plant communities or consistent populations of indicator species rather than individual specimens which may not be typical. Perennial weeds which may have colonised an area for some time are also a more reliable form of indicator than annual weeds which may have only been there for that year and thus indicate a temporary condition. In agriculture, a cover crop is grown to protect land from soil erosion and leaching of nutrients. ... Soil pH is an indication of the alkalinity or acidity of soil. ... A Red Valerian, a perennial plant. ...

Examples

• Fertile soil supports plants such as nettles, chickweed, groundsel and fat hen.

• Nitrogen-deficient conditions are indicated by the presence of nitrogen fixing legumes such as clovers or vetches.

• Bluebells are very competitive, in other words whenever they occur, they occur frequently.

• Bracken, plantains, sorrel, knapweeds, rhododendron and cranberries are amongst the plants that favour acidic conditions, whilst alkaline conditions tend to support populations of perennial sow thistle, bladder campion, henbane and mustard.

• Waterlogged or poorly drained land is indicated by the presence of species such as mosses, creeping buttercup and horsetail, or bog loving plants including sedges, rushes, marsh marigold, marsh orchid or flag iris.

See also: Organic gardening Species See text Nettle (Urtica) is a genus of flowering plants in the family Urticaceae, mostly perennial herbs but some are annual and a few are shrubby. ... Stellaria Categories: Plant stubs | Caryophyllales ... Binomial name Senecio vulgaris Groundsel (Senecio vulgaris) is a cosmopolitan (world-wide) annual weed of cultivation in the family Asteraceae. ... Binomial name Chenopodium album L. Fat Hen (Chenopodium album), also called white goosefoot, lambs quarters, lambsquarters, or pigweed, is a fast-growing, upright, weedy annual species of goosefoot, very common in temperate regions, growing almost everywhere in soils rich in nitrogen, especially on wasteland. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... Varieties of soybean seeds, a popular legume A flowering legume The term legume has two closely related meanings in botany, a situation encountered with many botanical common names of useful plants whereby an applied name can refer to either the plant itself, or to the edible fruit (or useful part). ... Clover (Trifolium) is a genus of about 300 species of plants in the pea family Fabaceae. ... Binomial name Vicia sativa Vetch or tare is a nitrogen fixing leguminous plant. ... The term bluebell can refer to the following: English Bluebell (Hyacinthoides non-scripta) or Spanish Bluebell () Bluebell of Scotland (Campanula rotundifolia, called harebell in England) and other Campanula species Virginia Bluebell (Mertensia virginica) Bluebell The name of one of the rabbits in the book Watership Down by Richard Adams BlueBell... Species Pteridium aquilinum Pteridium caudatum Pteridium latiusculum and about 7-8 other species Brackens (Pteridium) are a genus of about ten species of large, coarse ferns, in the family Hypolepidaceae. ... Species About 200 species, including: Plantago affra Plantago alpina Plantago arborescens Plantago arenaria - Branched Plantain Plantago argentea Plantago asiatica Plantago coronopus - Buckshorn Plantain Plantago cynops Plantago lanceolata - Ribwort Plantain Plantago major - Greater Plantain Plantago maritima - Sea Plantain Plantago maxima Plantago media - Hoary Plantain Plantago nivalis Plantago psyllium - Sand Plantain Plantago... Binomial name Rumex acetosa The common sorrel, or spinach dock, is a perennial herb, which grows abundantly in meadows in most parts of Europe and is cultivated as a leaf vegetable. ... Categories: Plant stubs | Asteraceae ... Subgenera Azaleastrum Candidastrum Hymenanthes Mumeazalea Pentanthera Rhododendron Therorhodion Tsutsusi Source: RBG, Edinburgh Rhododendron (from the Greek: rhodos, rose; dendron, tree) is a genus of flowering plants in the family Ericaceae. ... Species Vaccinium macrocarpon Vaccinium microcarpum Vaccinium oxycoccus The cranberries are a group of evergreen dwarf shrubs in the genus Vaccinium subgenus Oxycoccus, or in some treatments, in the distinct genus Oxycoccus. ... Species Sonchus asper (spiny sow thistle) Sonchus arvensis (field or perennial sow thistle) Sonchus dregeanus Sonchus integrifolius Sonchus nanus Sonchus oleraceus (common sow thistle) Sonchus wilmsii (milk thistle) Sow thistle (less commonly hare thistle or hare lettuce) is the common name for a number of related annual herbs in the... Binomial name Hyoscyamus niger L. Henbane (Hyoscyamus niger) is a plant of the family Solanaceae that originated in Eurasia. ... For the plant and spice of the same name, see the article on mustard. ... Jump to: navigation, search Subclasses Andreaeidae Sphagnidae Tetraphidae Polytrichidae Buxbaumiidae Bryidae Archidiidae Moss on a rock Mosses belong to the non-vascular plants. ... Binomial name Ranunculus repens S.Watson The Creeping buttercup (Ranunculus repens) is a flowering plant of the genus Ranunculus. ... Species Subgenus Equisetum Equisetum arvense - Field or Common Horsetail Equisetum bogotense - Andean Horsetail Equisetum diffusum - Himalayan Horsetail Equisetum fluviatile - Water Horsetail Equisetum palustre - Marsh Horsetail Equisetum pratense - Shade Horsetail Equisetum sylvaticum - Wood Horsetail Equisetum telmateia - Great Horsetail Subgenus Hippochaete Equisetum giganteum - Giant Horsetail Equisetum myriochaetum - Mexican Giant Horsetail Equisetum hyemale... Genera See text The Family Cyperaceae, or the Sedge family, is a taxon of monocot flowering plants that superficially resemble grasses or rushes. ... Genera Andesia Distichia Juncus - Rush Luzula - Woodrush Marsippospermum Oxychloë Prionium Rostkovia The Juncaceae, or the Rush Family, is a rather small monocot flowering plant family. ... Binomial name Caltha palustris L. The marsh marigold or Caltha palustris is a perennial herbaceous plant of wet places with large attractive yellow flowers borne in late spring. ... The Blue flag iris (Iris versicolor, also known as the wild iris) is a member of the Iris family native to Canada and America. ... Organic gardening is gardening that uses substantial diversity in pest control to reduce the use of the weapon of pesticides and tries to provide as much fertility with local sorces of nutrients rather than purchased fertilizers. ...