Puschkinia Bulb Planting: When And How To Plant Puschkinia Bulbs
Invasive plants are those that have become established in new areas or have spread from one area into another. They may not be native to the area they’re planted in, but their seeds germinate easily and quickly and once established they reproduce rapidly. Invasive species pose a threat to local ecosystems because they compete with native plants and animals, damage crops and other agricultural products, cause property damage, pollute water supplies and soil quality, destroy habitat for threatened or endangered species, and can even threaten human health.
Native plants provide food for wildlife such as birds and mammals. Native plants also protect us from harmful insects and diseases. Invasive species, however, often compete with native plants for resources like sunlight and nutrients. These competing species can reduce the amount of food available to native plants.
For example, some invasive weeds can eliminate many of the desirable wildflowers in a landscape. Other invasives can compete directly with our crops by eating them or damaging them through disease or insect attack.
Invasive plants can also harm local ecosystems by changing the food chain. In the case of purple loosestrife, its root secretions can act as a natural herbicide. It will eliminate surrounding plants by killing them directly when their roots take up the secreted chemicals. This allows loosestrife to grow with little competition around it and makes it a formidable invasive.
This example also shows how an invasive plant can alter an entire ecosystem. Without the native plants, there will be no food for the animals that eat them. Without animals feeding on them and distributing their seed, the surrounding area’s soil can become depleted of the nutrients necessary to support other plants. Even wind-blown seeds from distant places can’t help repopulate the area because they can’t sprout in loosestrife’s toxic environment.
Many invasives harm agricultural crops by transmitting disease or directly consuming the crop. For example, kudzu is an invasive species that was originally introduced to the U.S. to help control soil erosion.
Since it is a very fast growing vine, it has been used for a variety of purposes including making ropes. Unfortunately, it has become naturalized and spread out of control, running up trees and smothering the vegetation that grows nearby. Now it is considered a major pest in the south. It has been blamed for causing significant financial losses due to its ability to grow over and smother agricultural crops such as peach trees, pastures, and row crops.
Invasive plants can also impact wildlife that depend on native plants for food or rely on them for shelter. For example, purple loosestrife was brought over from Europe as an ornamental plant and has become widespread throughout much of the U.S. Loosestrife grows in dense stands that can displace native plants that are needed as food or shelter for wildlife.
The closely related spotted water hemlock is another invasive plant that has been spreading throughout the U.S. Recently spotted water hemlock has been linked to the deaths of several horses that apparently consumed some of the plants.
Some invasive plants, such as purple loosestrife and water hemp, produce a lot of seed. In fact, some can produce up to half a million seeds per plant! Many of these seeds can lie dormant in the soil for many years until the right conditions allow them to grow. Other invasive plants have extensive root systems that help them take up water and nutrients from deep in the soil.
This means they don’t need to expend energy growing roots near streams or other sources of water and can instead tap into deeper groundwater supplies. Since many native plants don’t have this capability, they can be out-competed for available water sources.
Just as some invasives spread rapidly, others can have devastating effects on a population quickly. This depends on the invasives’ life cycle and how it affects the environment around it. For example, yellow star thistle has become a major problem in many western states by out-competing many native plants and altering the soil pH. As the soil becomes more alkaline, it can no longer support the growth of other plants.
Yellow star thistle also produces a lot of seed and its deep taproot allows it to reach groundwater that other plants can’t get to. These two factors contribute to its spread and make it difficult to control.
Human-caused environmental changes can also contribute to invasions. For example, invasion of aquatic weeds in freshwater ecosystems has increased rapidly due to human alteration of these systems. Some examples include Eurasian watermilfoil, Australian swamp stonecrop, New Zealand pigmyweed and many types of algae.
Many marine invasions have been contributed to transportation linked to globalization. For example, the Pacific Northwest of the U.S. has been invaded by one of the most damaging marine species–Golden Jellyfish.
This jellyfish has been destroying fisheries in Japan for years, but fortunately, Japan’s colder waters have kept it from becoming established there. The warm waters of the Pacific Northwest, however, have enabled this species to thrive and reach incredible population densities in some locations.
Aquatic weeds can also have negative effects on commercial and recreational fisheries. One such invasive aquatic weed is water hyacinth, which has spread throughout much of the U.S. Water hyacinth produces a large number of floating leaves that can clog water ways, restricting the flow of water.
This can lead to low-oxygen conditions in lakes during the summer and promote the growth of harmful algal blooms. It also provides good cover for fish (such as bass) to hide under, which can make it more difficult for anglers to catch them.
Invasive plants and animals can also have detrimental effects on native species. One example is the population explosion of deer in the U.S. over the past few centuries.
Originally brought to the U.S. for hunting, deer were once kept in check by Native Americans and had limited range. Changes in land use and farming (elimination of predators and humans hunting) allowed their numbers to increase rapidly while humans took on the role of predator. Overbrowsing by deer can have a serious impact on plant communities both on the ground and in streams. In areas such as the Appalachians, overbrowsing by deer has contributed to loss of biodiversity by reducing the abundance of many native tree species.
Invasive plants and animals can lead to economic losses for humans. One example is zebra mussels, which have seriously damaged the water cooling systems of power plants across the U.S. by clogging pipes.
The economic impact has been estimated at several billion dollars.
Other examples of invasive species that are major contributors to environmental damage are feral pigs in the U.S., Atlantic cod in the North Atlantic, salt cedar (“saltbush”) in western U.S.
rivers, European rabbits in Australia, and miconia in Central and South America.
Eradicating some of these species has been attempted (in the case of miconia, with some success). In some other cases, the damage they have caused has been tremendous and there seems to be no way of ridding the environment of them (zebra mussels are very resistant to any attempts at eradication).
The increase in global trade and transportation that has accompanied globalization has had both positive and negative effects on the spread of invasive species. One of the more obvious effects is the increase in spread of non-native disease organisms (like the West Nile virus). Another major effect is the introduction of non-native marine species into new environments. The widening of the Panama Canal, for example, has allowed a whole host of marine species to move from the Pacific Ocean into the Caribbean Sea, and many of these (such as the lionfish) have had a major negative impact on local environments.
The spread of invasive species has several major effects on human populations. The most obvious is the direct effect on human health (zika virus spreading through Latin America is a recent example). Invasive species can also have drastic effects on local economies. The decline in Atlantic cod stocks is often attributed, at least in part, to the effects of invasive species (such as the sea lamprey and the cod worm), which were introduced through fishing.
Economies in many northern areas of Europe (such as the British Isles and Iceland) are still recovering from this collapse, and a similar pattern is emerging for Newfoundland fisheries.
Invasive species can also lead to loss of biodiversity as they displace native plants and animals. Finally, invasive species can directly affect human food security by competing with humans for food, both as producers and consumers of food (like the Asian longhorned beetle), or as a source of food for consumers (such as the zebra mussel).
Invasive species are a particular problem for island ecosystems, where their effects can be rapid and devastating. The introduction of rats to many islands has often resulted in the extermination of many native bird species. More generally, the loss of top predators from island ecosystems can result in a loss of balance that allows smaller predators to thrive (which may themselves destroy native species), increases competition for food by fast-breeding pests, or disease-carrying parasites, and a reduction in plants by destructive grazing animals.
Wetlands, estuaries and other coastal ecosystems are highly vulnerable to invasive species, which can have important negative effects on these fragile environments. One example of this is the introduction of the comb jelly, “Mnemiopsis leidyi”, to the Black Sea in the early 1980s. This species rapidly reproduced and made a diet of the larvae of many species of fish that inhabited the sea. Before the species was contained, it is thought to have caused the extinction of at least eleven species of fish, and severe declines in many more.
The most damaging category of invasive species, in terms of their economic and ecological impact, are the so-called “invasive weeds”. These are plants that spread rapidly, displace or poison crops (such as “Parthenium hysterophorus” in Australia), spread disease (such as “Plasmodiophora” in Brazil), or simply out-compete native plants.
Between 18500 and 12000 years ago, the planet was changing from being in the grip of a glacial period to a warmer interglacial one. During this period, many large mammals that previously existed went extinct (including the woolly mammoth, woolly rhinoceros, cave bear and steppe bison). It is assumed that human hunters, travelling in pursuit of prey species, were a factor in this extinction.
One proposed explanation for this rapid spread of animals is the hunting hypothesis. The idea is that humans hunted large mammals that would have otherwise have been prey, and so as their primary food source diminished through hunting, they would then move to other areas in search of food. This then lead them to encounter and hunt even more animals. This is suggested as a possible cause as it fits with the evidence, such as the fact that the animals largely disappeared towards the east (where they were heading as the climate grew colder), and that several species of animals became extinct on wide areas, not just particular regions.
An opposing view, the blitzkrieg hypothesis, states that it was unlikely that human could have caused such a large-scale extinction alone. They claim that the suddenness of the event, spread over a wide geographic region and the fact that many animals went extinct on oceanic islands without any evidence of human presence, points to some type of global climate change as the cause.
Both views continue to be debated, although it is generally (but not universally) accepted that humans did have a part to play in the extinction of these animals.
Genetically engineered crops are plants that have been modified for humans to benefit from in some way. This can mean being bigger and contain more of certain nutrients, being resistant to certain types of disease, or even containing more sugar. In the past fifty years alone, the amount of genetically modified crops being grown worldwide has increased rapidly. In the 1990s, the amount was around 1% of global crop growth, in 2009 it was 90%.
Among the most widely grown are:
Genetically modified crops are widely used, but there is still much debate over their use. One argument for their use is that it means that less land has to be used to farm animals and grow food for humans, therefore saving land for other things. They also can have benefits for humans in that they can contain more nutrients per crop.
However, there are a number of arguments against their use. One is that we don’t actually need these extra nutrients, or that we should be getting them from another source (such as eating less, or eating better). Another is that the increased use of pesticides and herbicides that often accompanies the growing of these crops can have a negative effect on the local environment (some even going so far as to say that they are having a massive effect on the world’s bee population). Another is that these crops can lead to larger companies controlling the world’s food, with smaller companies unable to keep up.
Finally, there is debate about the safety of these crops for human consumption and their impact on the environment once they have passed through our digestive systems.
These are just some of the many arguments for and against the use of these crops.
Genetically Modified Organisms, or GMOs for short, are organisms (usually plants) that have had their genetic material altered in some way, often through the use of a virus containing the genes that are to be incorporated into the genome of the host. This integration of alien DNA is then passed onto future generations.
These GM plants are used for a number of reasons. Some are used to supply bigger yields of certain nutrients, such as the insulin-producing GM-mushrooms that were created in the wake of the Bird-Flu epidemic. Other GMO plants are engineered for their resistance to disease or ability to withstand harsher growing conditions.
Since the 1990s, most of the GM crops being grown worldwide have been engineered to contain their own pesticides or to be resistant to herbicides.
GMOs have become increasingly controversial over the last few decades, with many people claiming that they can cause allergic reactions and diseases and also questioning whether they are safe to eat. Some GMOs, such as golden rice, have also faced opposition from people arguing that they take money and resources away from other methods of increasing food production to solve world hunger.
For most of the last century, world population growth has exponentially increased, meaning that food production has had to increase at the same rate if the seven billion people on Earth today are to be adequately fed. However, due to increasing pressure on land available for farming and climate change having a negative effect on agriculture in general, it is predicted that current food production levels will not be able to keep up with the ever-increasing need.
As such, the planet’s population faces the real threat of famine on a scale that we have not seen since the dark ages. Already hundreds of millions of people are malnourished or starving and this is set to get worse as the gap between food production and population growth widens to an unbridgeable chasm.
The following are just a few examples of how food production is set to struggle to keep up with our needs.
Climate change is having a significant negative impact on our food production. Not only will climate change help to make parts of the world too hot to grow crops, but it also has the potential to wipe out vast areas of farmland by making everything either too dry or too wet.
Rainfall in North America, for example, has increased by over 10% since the start of the twenty-first century. This may not sound like much, but it has been just enough to cause flooding in many areas and make once-arable land useless for farming.
Climate change is predicted to increase the effects of existing problems such as drought in Africa, with the Sahel desert spreading south by up to 70 kilometres a year.
The melting of the polar ice caps is also causing sea levels to rise, which will lead to coastal erosion and saltwater contamination of underground water tables essential for crop irrigation.
As sea water rises, fresh water is becoming a scarce resource. Many countries, including the UK and the US, have already begun implementing water restrictions to ensure that their growing populations have enough drinking water. In many parts of the world it is expected that the amount of available fresh water will be insufficient to meet population needs by as early as 2025.
The combination of water shortages and climate change leading to desertification will see an increase in ‘dust bowls’ around the world. These are regions characterised by dehydrated, eroded soil with little to no vegetative cover, which means that agricultural activity is no longer possible.
Water shortages and desertification will see an increase in global food prices as the quantity available cannot keep up with demand.
A major cause of hunger and malnutrition in sub-Saharan Africa is the luxury consumption of animal products, such as meat and dairy, by countries in the West.
Sources & references used in this article:
Behavior of supernumerary chromosomes in Puschkinia libanotica by GM Vernon, ER Witkus – Bulletin of the Torrey Botanical Club, 1970 – JSTOR
582. PUSCHKINIA PESHMENII: Hyacinthaceae by CG Vosa – Chromosomes today, 1969 – Elsevier/North Holland Biomedical …
Effects of planting depth and mulching on perennialization on several small geophyte species by M Rix, B Mathew – Curtis’s Botanical Magazine, 2007 – JSTOR
Flower bulbs worldwide: perspectives on the production chain and research by CT Miller, JJ Griffin, WB Miller – … Symposium on Flower Bulbs and …, 2016 – actahort.org