Ferns in general may be thought of as largely being specialists in marginal habitats, often succeeding in places where various environmental factors limit the success of flowering plants. The embryonic plant depends upon the prothallus for water and nutrients. Unfortunately, our editorial approach may not be able to accommodate all contributions. Ferns and Fern Allies of Pennsylvania. There are several mechanisms ferns use to prevent self-fertilization and the resulting homozygosity.
This is referred to as Equisetopsida sensu lato to distinguish it from the narrower use to refer to horsetails alone, Equisetopsida sensu stricto.
Fern Life Cycle.
Ferns are generally not known to be poisonous to humans. Prothalli, which are capable of photosynthesizing their own food and are free living plants, are features of every fern's life history. Subsequently, a consensus group was formed, the Pteridophyte Phylogeny Group PPGanalogous to the Angiosperm Phylogeny Grouppublishing their first complete classification in November Leaves are divided into two types a trophophyll and a sporophyll. Traditionally, three discrete groups have been denominated ferns: Formerly, the group was designated as division Pteridophtya, but their phylogenetic relationships remain unresolved. Views Read Edit View history.