Mosses were the first plants that managed to survive on the solid ground. The sporophyte forms from a fertilized egg inside the flask-like archegonium and attaches to the gametophyte via a penetrating foot.
The sporophyte receives nourishment from the gametophyte. The sporophyte forms a very small stalk called a seta and a single sporangium. Botanically, mosses are non-vascular plants in the land plant division Bryophyta. They are small a few centimeters tall herbaceous non-woody plants that absorb water and nutrients mainly through their leaves and harvest carbon dioxide and sunlight to create food by photosynthesis. A After applying a mosskiller, any moss in the lawn will turn black and die.
However, it will be necessary to rake out the dead moss as its presence will continue to hinder the growth of the lawn. To keep your moss healthy, simply mist the plant regularly and give it a good watering about twice a week. Mosses also have different mechanisms they use for acquiring nutrients.
Some mosses are able to take up nutrients from water flowing over them, thus they have very effective absorptive surfaces. Other mosses, such as Polytrichum , sequester nutrients directly from the soil or substrate on which they are growing and transfer the nutrients to their growing tips. With this in mind we can see that the physical and chemical nature of the substrate as well as its water holding capacity are extremely important in establishment of mosses.
Where do mosses live? Now that we have seen the resilience mosses possess via their multiple modes of reproduction, it is easier to fathom that mosses can live anywhere from the Arctic Circle to the tropical forests at the equator. Mosses can be found around hot springs, at the bottom of lakes, on rocks, sand dunes, trees and, even in a few cases, sea water. And of course those of us who live in the Pacific Northwest know that mosses thrive in moist temperate forests.
An opportunist, mosses grow on our trees, sidewalks, garden, rooftops, and everywhere in between. The two main requirements of a moss are sufficient moisture and accessible nutrients. For example, the moist environment of a rooftop shaded by trees seems just fine for mosses. Not only does the rooftop stay perpetually moist, but nutrients are also supplemented from the ash that fireplace chimneys produce Schofield, See section regarding Mosses on Rooftops.
Shingles composed of wood, asbestos, and conglomerate composition all make suitable homes for moss; however, metallic roofs or those with an abundance of tar will discourage moss growth.
But the tarred roof must be smooth to assure that mosses will not colonize in the cracks and crevices. Mosses prefer to colonize shingles above the eaves, on detritus that builds up in the eaves' troughs or other depressions.
Mosses will be at their best in the winter when there is plenty of water, little light, and low temperatures. In summer mosses dry out and become dormant. What are mosses good for? Unknown to most of us, mosses actually have many uses, from ecological to medical with a suite of common household uses in between. One of the better known ecological uses of moss is as bioindicators of air pollution, such as those caused by factory emissions.
They are very good indicators of acid rain damage to an ecosystem as well. Mosses are also used as erosion control agents as they aid in moisture control and stabilization of soil that would either be wind blown or washed away by water.
Identify microphylls. Do the specimens have any strobili? Be sure to look up these words if you do not understand them. Observe a specimen of a spike moss such as Selaginella. Note the structure of the microphylls. Skip to main content. Module 4: Seedless Plants.
Search for:. Reading: Seedless Plants Introduction Plants kingdom Plantae are autotrophs ; they make their own organic nutrients. Some evidence that suggests that plants evolved from the green algae is: they both use chlorophyll a, chlorophyll b, and carotenoid pigments during photosynthesis.
These traits occur in plants but not charophyceans. Some evolved independently in other algae. Apical meristems Alternation of generations Spores with protective walls Spores produced in sporangia Gametes are produced in multicellular structures called gametangia; Antheridia produce sperm; Archegonia produce eggs Multicellular dependent embryos Many have a cuticle that waterproofs and offers some protection Alternation of Generations The basic alternation of generations life cycle is illustrated below.
Figure 1. Moss growing on a rock. Figure 2. Moss gametophytes and sporophytes. Figure 3. Mnium a moss antheridial head. Figure 4. Mnium a moss antheridial head x Figure 5. Figure 6.
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