Not to be semantically confused with : Alpine Bistort (Persicaria vivipera) [a plant with similar name belonging to a differing family]

Some similarities to : Bugle (Ajuga reptans) which has similar dark-green leaves which are also similarly shaped and with rounded teeth, and a similar flower spike but with blue rather than purple flowers.

Not directly related to : Red Bartsia (Odontites vernus) nor to Yellow Bartsia (Parentucellia viscosa) [plants with a similar hemi-parasitizing predisposition belonging to differing Genera but which all belong to the Broomrape Family (Orobanchaceae)].

Occupies basic limestone areas rather than acidic on upland damp grassland in Northern England and rocky ledges in Scotland. It occurs in small marshes flushed with water from underlying (but higher) limestone rocks such as by calcareous springs. It is a very rare ( [RRR]) and is protected.

Alpine Bartsia is a  Hemi-parasitic plant, meaning that it can derive some of its nutrients from the roots systems of other nearby plants which it has hijacked by means of its underground horizontal rhizomes. But it is capable of surviving without parasitizing another plant. Chlorophyll is present and it is capable of photosynthesis by itself; it is a chlorophyllous parasitic. Moreover, it is thought that, in the case of Alpine Bartsia, it goes further than that, it seems to actively encourage other plants to grow nearer to it presumably in order to be able to parasitize them. This may or may not be the case for other parasitic and hemi-parasitic plants, but it would certainly be advantageous for them to so do, providing the other plants don't out-grow it shading it from light. But perhaps it also stunts their growth, by means of tapping part of the nutrients from the other plant, and perhaps by chemical means also. But it has been proved that the plant litter of decomposing Alpine Bartsia releases nutrients into the soil which encourage the growth of other plants around it.

Your Author pontificates:
Many plants seem to employ methods of chemically signalling to each other (mainly between the same plants, but there is no reason to suppose that that will not include dissimilar plants as well). Much is still to be learned about chemical signalling, which occurs both through the soil, and through the air, and probably by being in direct physical contact as well, which is how parasitic plants accomplish the task.

The hosts of Alpine Bartsia include distinguished species such as (Angelica sylvestris), (Cirsium palustre), (Filipendula ulmaria), (Lotus pedunculatus), (Mnium longirostrum) and (Carex capillaries) but basically any grasses and whatever might happen to be growing nearby, or can be coaxed into growing nearby. It forms dense clones by means of these rhizomes.

MONOTERPENOIDS The following odorous and volatile monoterpenes and terpenoids were discovered in an extract from the plant: α-Pinene, Z-3-Hexenol, Z-3-Hexenyl Acetate, PhenylAcetaldehyde and PhenylAcetonitrile. (Z)-3-Hexenol (aka cis-Hexen-1-ol and Leaf Alcohol) smells of freshly cut green grass and is produced in small amounts by many differing plants. It is used as an aroma compound in the flavouring of foods and perfumes to embellish fruity or vegetable odours. It also acts as an attractant to many insects, who flock to eat whatever plant is producing the chemical. The Acetic Acid ester of Leaf Alcohol is Leaf Aldehyde (aka (Z)-3_Hexenyl Acetate or cis-3-Hexenal) and has a similar but more powerful aroma. It is however unstable and reverts to the trans isomer trans-2-Hexenal. Phenylacetaldehyde is an aromatic compound found in many plants including Buckwheat and is also found in chocolate. It is also added to some cigarettes in an attempt to improve their unpalatability. It is used as a pheromone by many insects. It has a sweet smell reminiscent of honey or roses. Phenylacetonitrile (aka Benzyl Cyanide) is a toxic volatile colourless oily liquid and is also an irritant to skin and the vapours to the eye. Burning it releases Hydrogen Cyanide, HCN, which is a very poisonous gas.

Three Iridoid glycosides and two PhenylPropanoid derivatives were also found. A crude extract of Alpine Bartsia also yielded Melampyroside, Mussaenoside, Mussaenosidic Acid, 8-epi-Loganin; the flavonoids Apigenin and Luteolin and its 7-O-β-glucopyranoside, and Benzoic Acid.