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Woodland hike in Bell Park on a sunny SundayLaura and I enjoyed a Sunday walk at Bell Park on the route to Mount Uniacke Estate. It is a richly forested area with good trails and not too strenuous. This location also offers great winter photography especially by the lake. The highlight was meeting a colony of lycopods, from the family of clubmosses. Bell Park Sunday Hike
lycopods, from family of clubmosses
From Wikipedia, the free encyclopedia
This article is about a group of plants that excludes the extinct zosterophylls. For the more broadly defined group that includes the zosterophylls, see Lycophyte.
"Lycopod" redirects here. For other uses, see Lycopod (disambiguation).
Lycopodiopsida is a class of vascular plants also known as lycopods or lycophytes. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous, extinct tree-like forms (Lepidodendrales) formed huge forests that dominated the landscape and contributed to coal deposits. The nomenclature and classification of plants with microphylls varies substantially among authors. A consensus classification for extant (living) species was produced in 2016 by the Pteridophyte Phylogeny Group (PPG I), which places them all in the class Lycopodiopsida, which includes the classes Isoetopsida and Selaginellopsida used in other systems. (See Table 2.) Alternative classification systems have used ranks from division (phylum) to subclass. In the PPG I system, the class is divided into three orders, Lycopodiales, Isoetales and Selaginellales. CharacteristicsClub-mosses (Lycopodiales) are homosporous, but the genera Selaginella (spikemosses) and Isoetes (quillworts) are heterosporous, with female spores larger than the male.[1] As a result of fertilisation, the female gametophyte produces sporophytes. A few species of Selaginella such as S. apoda and S. rupestris are also viviparous; the gametophyte develops on the mother plant, and only when the sporophyte's primary shoot and root is developed enough for independence is the new plant dropped to the ground.[2] Many club-moss gametophytes are mycoheterotrophic and long-lived, residing underground for several years before emerging from the ground and progressing to the sporophyte stage.[3] Lycopodiaceae and spikemosses (Selaginella) are the only vascular plants with biflagellate sperm, an ancestral trait in land plants otherwise only seen in bryophytes. The only exceptions are Isoetes and Phylloglossum, which independently has evolved multiflagellated sperm cells with approximately 20 flagella[4][5] (sperm flagella in other vascular plants can count at least thousand, but is completely absent in seed plants except for Ginkgo and cycads).[6] Because only two flagella puts a size limit on the genome, we find the largest known genomes in the clade in Isoetes, as multiflagellated sperm is not exposed for the same selection pressure as biflagellate sperm in regard of size.[7]
Keywords:
from the family of clubmosses,
Canada,
Fall Colours,
lycopods,
Nova Scotia,
Parks of Nova Scotia,
Woodland Walk In Bell Park
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