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Lamiaceae Taxonomy Browser
Hedeoma pulegioides (L.) Pers.
EOL Text
The most remarkable thing about this little plant is the strong scent of the foliage. Otherwise, it is rather easy to overlook. The only other species in this genus that occurs in Illinois, Hedeoma hispida (Rough Pennyroyal), has linear leaves and a milder scent; it also prefers sunnier habitats. American Pennyroyal superficially resembles Gratiola neglecta (Clammy Hedge Hyssop), but this latter species lacks any fragrance and its prefers soggy habitats (e.g., damp depressions in woodlands). Native pennyroyal species (Hedeoma spp.) have only 2 stamens per flower, while other similar species in the Mint family often have 4 stamens per flower. Because the flowers are so small, this requires a 10x hand lens to see clearly.
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/woodland/plants/am_pennyroyal.htm |
This native wildflower is a summer annual about 4-12" tall that is branched or unbranched. The stems are light green, terete, and pubescent. The opposite leaves are about 1" long and ¼" across; they are elliptic, oblong-lanceolate, or oblong-oblanceolate in shape. The margins of the leaves are smooth or they have a few blunt teeth toward their tips. The petioles of the leaves are short and slender. The foliage of American Pennyroyal has a strong medicinal-mint scent. Small axillary clusters of 1-4 flowers are produced from the base of each middle to upper leaf. Each flower is about ¼" long and half as much across, consisting of a 2-lipped tubular corolla, a tubular calyx with 5 teeth, 2 stamens, and a 4-celled ovary with a single style. The corolla is white or blue-violet with a contrasting color near its throat. Along the outer rim of the corolla, there is an upper lobe, 2 lateral lobes, and a lower lobe; they are short and rounded (although not always well-defined). The hairy ridged calyx has 3 upper triangular teeth and 2 lower teeth that are slender-lanceolate. At the base of each flower, there is a pair of a leafy bracts; these bracts are at least as long as the flower. The blooming period occurs from mid-summer to early fall and lasts 1-3 months; individual flowers are short-lived. At maturity, each fertile flower is replaced by 4 nutlets. This wildflower reproduces by reseeding itself. It occasionally forms colonies at favorable sites. Cultivation
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/woodland/plants/am_pennyroyal.htm |
American Pennyroyal is occasional to locally common throughout Illinois, except the NW section of the state, where it is less common (see Distribution Map). Habitats include dry upland woodlands, rocky woodlands, areas along woodland trails, rocky glades, areas along railroads, roadsides, pastures, and fallow fields. This species prefers areas (whether sunny or shaded) that have been subjected to some disturbance.
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/woodland/plants/am_pennyroyal.htm |
Canada
Origin: Native
Regularity: Regularly occurring
Currently: Present
Confidence: Confident
United States
Origin: Native
Regularity: Regularly occurring
Currently: Present
Confidence: Confident
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Hedeoma+pulegioides |
American Pennyroyal is occasional to locally common throughout Illinois, except the NW section of the state, where it is less common (see Distribution Map). Habitats include dry upland woodlands, rocky woodlands, areas along woodland trails, rocky glades, areas along railroads, roadsides, pastures, and fallow fields. This species prefers areas (whether sunny or shaded) that have been subjected to some disturbance.
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/woodland/plants/am_pennyroyal.htm |
Small bees pollinate the flowers, where they seek nectar and pollen. These visitors include Little Carpenter bees (Ceratina spp.), Halictid bees (Augochlorella spp., Halictus spp., & Lasioglossum spp.), and the Dagger bee Calliopsis andreniformis. Syrphid flies may visit the flowers occasionally, but they feed on the pollen and are less effective at pollination. The strong scent of the foliage protects this plant from mammalian herbivores. Photographic Location
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/woodland/plants/am_pennyroyal.htm |
Hedeoma pulegioides (American Pennyroyal)
(Bees collect pollen or suck nectar; Syrphid flies feed on pollen & are non-pollinating; all observations are from Robertson)
Bees (long-tongued)
Anthophoridae (Ceratinini): Ceratina dupla dupla sn
Bees (short-tongued)
Halictidae (Halictinae): Augochlorella aurata sn cp fq, Augochlorella striata sn, Halictus ligatus sn, Lasioglossum tegularis sn cp, Lasioglossum versatus sn cp; Andrenidae (Panurginae): Calliopsis andreniformis sn fq
Flies
Syrphidae: Toxomerus marginatus fp np
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | Copyright © 2002-2015 by Dr. John Hilty |
| Source | http://www.illinoiswildflowers.info/flower_insects//plants/am_pennyroyal.htm |
Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 4
Species With Barcodes: 1
Canada
Rounded National Status Rank: N4 - Apparently Secure
United States
Rounded National Status Rank: N5 - Secure
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Hedeoma+pulegioides |
Rounded Global Status Rank: G5 - Secure
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | NatureServe |
| Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Hedeoma+pulegioides |