Biodiversity
"Biodiversity starts in the distant past, and it points towards the future."
- Frans Lanting
- Frans Lanting
Introduction
Biodiversity is biological diversity (see what they did there?) as evidenced by the number of different species of plants and animals in a given environment. The importance of biodiversity in the world cannot be understated. Ecosystems on our beautiful planet have developed as an intricate, delicate systems of checks and balances of species of plant and animal life. Fostering biodiversity is one of the most important ways to build a healthy garden, free of pests and disease. Watch the video below to learn more about the importance of biodiversity around the world:
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As you can see, biodiversity is what keeps the world spinning, so to speak. And although it may seem like a small gesture in such a large world, encouraging biodiversity in your yard can actually have a very positive impact on the ecology in your neighborhood. The first step to encouraging biodiversity in your garden is planting species that are native to your area. This will begin to bring in insects and animals that thrive around these plants. |
Our gardens are unique cultivated microclimates, each with their own level of biodiversity. Backyard by backyard and neighborhood by neighborhood, when gardeners increase biodiversity in their landscapes, they create stepping stones that connect formerly disjointed and isolated habitat islands. The cumulative efforts of individuals across the country planting native and pollinator gardens has the potential to begin reversing the habitat destruction and species loss that has occurred over the last century. The majority of the large natural habitats that once existed in our amazingly diverse country have been either completely lost or fragmented into small pockets by cities, farms, industry, and other human activity. Urban landscapes are sterile environments, stretching across what were once complex ecosystems supporting thousands of species. Wildlife that does exist in the isolated pockets of natural landscapes that still exist are more vulnerable to species decline, and any efforts made by home gardeners to remedy this sad situation are appreciated.
Starting with The Soil
Soil biodiversity is the term used to describe the variety of life below ground in the soil. It includes the genetic biodiversity, the species diversity and the diversity of the whole soil ecosystem. The biodiversity of soils is one of nature's most amazing assets. Imagine a spoonful of good garden soil - there are likely to be more organisms in that small amount of soil than there are people on the entire planet. But it is not only the total numbers in soil that are amazing. It is also the number of different species that occur. There may be, for instance, in a three foot by three foot piece of garden soil 100 species of worms (earthworms, nematodes, enchytraeids); 100 species of mites; and hundreds, even thousands, of species of bacteria and fungi. The variety and numbers of creatures that live in the soil is mind-boggling.
Together these organisms develop what is known as the food chain or food web. Each group of organisms has a well-defined responsibility for the breakdown of plant material, the formation of humus, and the release and cycling of nutrients. Thus as soon as plant material falls to the surface, it is attacked by the larger soil fauna such as earthworms, mites, enchytraeids and these organisms begin the process of breakdown and stimulate microbial activity. As the breakdown proceeds, the micro-fauna come into action together with the microflora, both eventually enabling nutrients to be released and made available to plant roots as well as providing food for the organisms themselves. The breakdown of organic matter and the recycling of nutrients depends on a complex network of interactions between the larger organisms such as earthworms and mites and the microorganisms including bacteria and fungi. Although it is well known that this network occurs, we are still a long way from unravelling the complex network of interactions.
Each soil type and the vegetation it supports will have its own biodiversity. This biodiversity will be very different between, say a pine forest, a forest of oak trees, and a tropical rainforest. The organisms will have adapted to the needs of the forest and in turn the forests and the soils in which they grow will be important in providing the habitat for these organisms. There will also be a significant difference between the biodiversity in a forest, a meadow or a farmer's cultivated field. The fact that there are these differences is well known but there are many things about biodiversity that we do not know. For example, we have very little idea of the numbers of organisms in soils, the number of species of organisms, the exact roles of the different species and what the impact of removing a particular species from the soil would be. Soil has been termed 'the last biotic frontier'; the danger is that until we know much more about the roles of the organisms and the effect that changing land use, for example, will have on them, we run a great risk of damaging for ever vital parts of the soil biotic system.
Without living organisms in soil, it would simply be crushed rock, and debris would not decompose. Soil without life in it is considered to be 'dead' soil, and will not support plant life, no matter how much fertilizer is used.
Above the Surface
Many beneficial organisms call gardens their home, and as we work outdoors, we will notice the many signs that they are there, even if we don't see them. This group of individual insects, arachnids, and animals forms a landscape army of predators, pollinators, and sometimes pests. Unfortunately, in our drive to rid our gardens of damaging organisms, we have also created an environment that is not conducive to supporting the 'good guys' either. Removing an aphid infestation, for example, takes away an important food source for ladybugs visiting your yard. Many of the organisms below are also harmed by the use of pesticides and other garden chemicals, wiping out entire colonies or generations. The insects and animals outlined below represent the most important workers in the home garden. They call your garden their home, and they treat it with the utmost respect, assisting in pollination, fertilizing the soil, controlling pest populations, and contributing to the overall health and biodiversity of outdoor spaces.
Bees
Bees are some of the most invaluable living beings on this earth. Bees are immensely helpful, assisting in pollination of plants that constitute about a third of our daily diet. They are so beneficial, in fact, that fruit farmers will regularly set up beehives near their crops to ensure a healthy harvest. Bees have been around since the Jurassic period and evolved alongside flowers. Some species (such as Honeybees, Stingless Bees, and Bumblebees) have highly organized colonies, made up of a Queen Bee, female worker bees (who guard the hive and forage) and male drones (who mate with the queen). There are also species of bees which are solitary, including Mason Bees, Carpenter Bees, and Leafcutter Bees. To learn more about these busy garden inhabitants, check out the page linked below:
Bees are some of the most invaluable living beings on this earth. Bees are immensely helpful, assisting in pollination of plants that constitute about a third of our daily diet. They are so beneficial, in fact, that fruit farmers will regularly set up beehives near their crops to ensure a healthy harvest. Bees have been around since the Jurassic period and evolved alongside flowers. Some species (such as Honeybees, Stingless Bees, and Bumblebees) have highly organized colonies, made up of a Queen Bee, female worker bees (who guard the hive and forage) and male drones (who mate with the queen). There are also species of bees which are solitary, including Mason Bees, Carpenter Bees, and Leafcutter Bees. To learn more about these busy garden inhabitants, check out the page linked below:
Please note: Although bees are beneficial to your garden, cultivating a bee-friendly habitat is under no circumstances more important than your health. If you are allergic to bees or have friends and family who are who frequently visit your yard, take the necessary precautions to keep everyone safe.
Wasps
Wasps are distinguished from bees with their slender, hairless bodies that are sometimes segmented. Although many of these insects are killed each year due to their more aggressive predisposition and their carnivorous appetite that brings them into close proximity to barbecue-goers, they are actually beneficial in a few ways. First, although they do not have the necessary hairs on their bodies to enhance pollination in the garden on many plants, on flowers like the sunflower that only require a simple 'brush' to pollinate, they can do a lot of good. They also feed on house fly larvae and harmful garden insects that can wreak havoc on your blooms. Hornets and Yellow Jackets are included in this group of flying insects.
Wasps are distinguished from bees with their slender, hairless bodies that are sometimes segmented. Although many of these insects are killed each year due to their more aggressive predisposition and their carnivorous appetite that brings them into close proximity to barbecue-goers, they are actually beneficial in a few ways. First, although they do not have the necessary hairs on their bodies to enhance pollination in the garden on many plants, on flowers like the sunflower that only require a simple 'brush' to pollinate, they can do a lot of good. They also feed on house fly larvae and harmful garden insects that can wreak havoc on your blooms. Hornets and Yellow Jackets are included in this group of flying insects.
Please note: Although wasps can be beneficial to your garden, cultivating a welcoming wasp habitat is not more important than your health. If you are allergic to wasps or have friends and family who are who frequently visit your yard, take the necessary precautions to keep everyone safe.
Butterflies
Like bees, butterflies are great pollinators. These insects have large, brightly colored wings and live on an all-liquid diet of nectar. An abundance of butterflies in an area is a good sign that the local ecosystem is thriving. Butterflies are generally considered to be solitary insects, and do not form colonies, though their social behavior can change somewhat depending on the species and setting they are observed in. Their wings fold together when at rest, sometimes hiding their bright colors. Although butterflies do not consume pollen, they do visit nectar-producing flowers, and will unwittingly collect pollen grains on their legs and transfer them to the next flower they visit.
Like bees, butterflies are great pollinators. These insects have large, brightly colored wings and live on an all-liquid diet of nectar. An abundance of butterflies in an area is a good sign that the local ecosystem is thriving. Butterflies are generally considered to be solitary insects, and do not form colonies, though their social behavior can change somewhat depending on the species and setting they are observed in. Their wings fold together when at rest, sometimes hiding their bright colors. Although butterflies do not consume pollen, they do visit nectar-producing flowers, and will unwittingly collect pollen grains on their legs and transfer them to the next flower they visit.
Beetles
Beetles are insects that have two sets of wings, a hardened outer pair and a membranous inner pair. They are found in every habitat worldwide, except for totally arid or frozen regions of the globe. Beetles feed on plants and fungi, break down animal and plant debris, and feed on other invertebrates. Some are serious pests, and others are beneficial to garden ecosystems.
Beetles are insects that have two sets of wings, a hardened outer pair and a membranous inner pair. They are found in every habitat worldwide, except for totally arid or frozen regions of the globe. Beetles feed on plants and fungi, break down animal and plant debris, and feed on other invertebrates. Some are serious pests, and others are beneficial to garden ecosystems.
Spiders
Spiders, or arachnids, are organisms that have eight legs, mouthparts with fangs, and are found in almost every habitat worldwide. Most species form webs of some kind. Unlike insects, spiders do not have antennae, and instead sense the environment around them through special sensors on their legs called pedipalps. They are generally solitary and cannibalistic, though there are some species that are social and form colonies. They are commonly killed due to their cultural reputation as monsters or organisms that will seek out and attack humans, but this is far from the truth.
Spiders, or arachnids, are organisms that have eight legs, mouthparts with fangs, and are found in almost every habitat worldwide. Most species form webs of some kind. Unlike insects, spiders do not have antennae, and instead sense the environment around them through special sensors on their legs called pedipalps. They are generally solitary and cannibalistic, though there are some species that are social and form colonies. They are commonly killed due to their cultural reputation as monsters or organisms that will seek out and attack humans, but this is far from the truth.
Birds
This group of organisms is warm-blooded, have feathers, produce offspring through egg-laying, and strong but lightweight skeletons. Not all birds fly, but most have the ability to do so. They are generally social, communicating with calls and chirps, and cooperate to reproduce, hunt, defend their territory, and fight off predators. Birds are the only living dinosaurs on earth today, and there are many species found in California, listed on the page below.
This group of organisms is warm-blooded, have feathers, produce offspring through egg-laying, and strong but lightweight skeletons. Not all birds fly, but most have the ability to do so. They are generally social, communicating with calls and chirps, and cooperate to reproduce, hunt, defend their territory, and fight off predators. Birds are the only living dinosaurs on earth today, and there are many species found in California, listed on the page below.
Reptiles and Turtles
This group of cold-blooded vertebrates, most of which reproduce sexually (except for boas and pythons, which give live birth) and usually produce soft-shelled eggs. They have special skin made up of scales, bony plates, or both; they shed this skin periodically as they grow. They regulate body temperature by moving to warmer or cooler environments. Reptiles are considered beneficial to garden ecosystems because they control populations of harmful insects.
This group of cold-blooded vertebrates, most of which reproduce sexually (except for boas and pythons, which give live birth) and usually produce soft-shelled eggs. They have special skin made up of scales, bony plates, or both; they shed this skin periodically as they grow. They regulate body temperature by moving to warmer or cooler environments. Reptiles are considered beneficial to garden ecosystems because they control populations of harmful insects.
Rodents & Small Mammals
Although these animals can be viewed as pests in the garden, they are also considered to be beneficial in many cases. These critters are warm blooded and give live birth to their young. Rodents are generally social animals, with complex methods of communicating with one another, and caring for their sick and injured.
Although these animals can be viewed as pests in the garden, they are also considered to be beneficial in many cases. These critters are warm blooded and give live birth to their young. Rodents are generally social animals, with complex methods of communicating with one another, and caring for their sick and injured.
Creating a Biodiverse Garden
A biodiverse garden is rich with life, and has an abundance of different plant and animal species that work together to create a holistic system of checks and balances. These gardens use different types of structures, groundcovers, plant families, and features to purposefully attract and enhance the local populations of creatures big and small. No matter the size of the outdoor space, it has the potential to be a host and haven for multiple species. Use the following suggestions to increase the biodiversity in your garden.
Discontinue Use of Chemicals
Natural landscapes have one glaring difference from urban landscapes - they are free of pesticides, herbicides, and other chemicals that we frequently find in our neighborhood soil, air, and water. In order to bring in wildlife to gardens, it is essential to stop using these products, and allow a full ecosystem to develop both above and below the soil. This includes the use of non-organic fertilizers, and, if possible, chemical controls of household pests. Organic alternatives include the use of compost instead of fertilizers, and the use of Integrated Pest Management practices to control pests and disease. Mulch can also be used to suppress weed growth instead of relying on herbicides.
Natural landscapes have one glaring difference from urban landscapes - they are free of pesticides, herbicides, and other chemicals that we frequently find in our neighborhood soil, air, and water. In order to bring in wildlife to gardens, it is essential to stop using these products, and allow a full ecosystem to develop both above and below the soil. This includes the use of non-organic fertilizers, and, if possible, chemical controls of household pests. Organic alternatives include the use of compost instead of fertilizers, and the use of Integrated Pest Management practices to control pests and disease. Mulch can also be used to suppress weed growth instead of relying on herbicides.
Let the Garden Relax
Allow plants in the garden to take on more of their natural form. Allow your grass to grow a little longer between mows, slack off on your deadheading routine, and let shrubs do their thing. This part of the process may be a little painful if you value order and perfection in the garden, but this exercise in messiness will pay off in the long run. Sometimes, it can even be fun to witness the small changes that occur in the garden due to simple light neglect. Letting lawns grow long benefits the immediate environment by reducing air pollution and providing shelter for pollinators and other important insects. Allowing shrubs to grow in invites more birds to safely navigate the property, and provides more food for them due to increased insect and spider presence in branch nooks.
Allow plants in the garden to take on more of their natural form. Allow your grass to grow a little longer between mows, slack off on your deadheading routine, and let shrubs do their thing. This part of the process may be a little painful if you value order and perfection in the garden, but this exercise in messiness will pay off in the long run. Sometimes, it can even be fun to witness the small changes that occur in the garden due to simple light neglect. Letting lawns grow long benefits the immediate environment by reducing air pollution and providing shelter for pollinators and other important insects. Allowing shrubs to grow in invites more birds to safely navigate the property, and provides more food for them due to increased insect and spider presence in branch nooks.
This laid-back step also applies to the soil in the space. If you haven't already, now is the time to move towards a low-till or no-till type of garden maintenance system. Rototilling all beds in a garden is extremely bad for biodiversity. Tilled soil is disturbed soil, and disturbed soil releases more moisture, has more surface area exposed to direct sunlight, undergoes increased erosion, and is not conducive to supporting the lives of microfauna. Increase your soil's resiliency even further by mulching with a 3-inch deep layer of organic material.
Add Native Plants
In order to bring in native species of animals and insects in, it is critical to add native plants to the landscape. Local wildlife is used to the textures, sights, and smells of these plants, having co-evolved with them. Native plants are the building blocks of wildlife friendly and biodiverse gardens, because they support a wide variety of life. Group together grasses and sedges and mass flowers for shows of colorful blooms. Grasses and sedges. Some to try: California fescue (Festuca californica), purple needlegrass (Nasella pulchra), blue-eyed grass (Sisyrinchium bellum), foothill sedge (Carex tumulicola), coast melic (Melica imperfecta). Mass flowers. You can really have some fun with these. Some to consider: red-flowered buckwheat (Eriogonum grande var. rubescens), California buckwheat (Eriogonum fasciculatum, look for a low-growing cultivar), California fucshia (Epilobium canum -- these bloom in late summer to fall!), harvest brodiaea (Brodiaea elegans, a bulb), wild hyacinth (Dichelostemma capitatum, another bulb), hummingbird sage (Salvia spathacea), one of the shrubby monkeyflowers (Mimulus spp.), coyote mint (Monardella villosa), black sage (Salvia mellifera) or any of the other California sages, margarita BOP penstemon (Penstemon sp.) or one of the many penstemons, California buttercup (Ranunculus californicus). Architectural plants for winter interest. I'm leaning more toward winter fruit producers. Some plants and small shrubs to ponder: western redbud (Cercis occidentalis), deer grass (Muhlenbergia rigens), California wild rose (Rosa californica), lemonade berry and sugar bush (Rhus integrifolia and R. ovata), currants and gooseberries (Ribes spp.), one of the smaller manzanita species (Arctostaphylos 'Howard McMinn', Arctostaphylos 'Sentinel', Arctostaphylos edmundsii var. parvifolia 'Bert Johnson').
In order to bring in native species of animals and insects in, it is critical to add native plants to the landscape. Local wildlife is used to the textures, sights, and smells of these plants, having co-evolved with them. Native plants are the building blocks of wildlife friendly and biodiverse gardens, because they support a wide variety of life. Group together grasses and sedges and mass flowers for shows of colorful blooms. Grasses and sedges. Some to try: California fescue (Festuca californica), purple needlegrass (Nasella pulchra), blue-eyed grass (Sisyrinchium bellum), foothill sedge (Carex tumulicola), coast melic (Melica imperfecta). Mass flowers. You can really have some fun with these. Some to consider: red-flowered buckwheat (Eriogonum grande var. rubescens), California buckwheat (Eriogonum fasciculatum, look for a low-growing cultivar), California fucshia (Epilobium canum -- these bloom in late summer to fall!), harvest brodiaea (Brodiaea elegans, a bulb), wild hyacinth (Dichelostemma capitatum, another bulb), hummingbird sage (Salvia spathacea), one of the shrubby monkeyflowers (Mimulus spp.), coyote mint (Monardella villosa), black sage (Salvia mellifera) or any of the other California sages, margarita BOP penstemon (Penstemon sp.) or one of the many penstemons, California buttercup (Ranunculus californicus). Architectural plants for winter interest. I'm leaning more toward winter fruit producers. Some plants and small shrubs to ponder: western redbud (Cercis occidentalis), deer grass (Muhlenbergia rigens), California wild rose (Rosa californica), lemonade berry and sugar bush (Rhus integrifolia and R. ovata), currants and gooseberries (Ribes spp.), one of the smaller manzanita species (Arctostaphylos 'Howard McMinn', Arctostaphylos 'Sentinel', Arctostaphylos edmundsii var. parvifolia 'Bert Johnson').
High and Low
Ensure that the landscape has a variety of heights throughout its span by adding groupings of trees and shrubs. These garden features will add leaves and twigs to the environment, making more habitat for birds and insects. These plants are also great at creating shade, which can increase soil moisture retention, keep temperatures in the garden down, and provide the shade needed to support a wider variety of plant life in the space. The impact of trees and shrubs can be multiplied by their flowering and fruiting qualities, which can have the added benefits of bringing in pollinators and providing food for wildlife.
Ensure that the landscape has a variety of heights throughout its span by adding groupings of trees and shrubs. These garden features will add leaves and twigs to the environment, making more habitat for birds and insects. These plants are also great at creating shade, which can increase soil moisture retention, keep temperatures in the garden down, and provide the shade needed to support a wider variety of plant life in the space. The impact of trees and shrubs can be multiplied by their flowering and fruiting qualities, which can have the added benefits of bringing in pollinators and providing food for wildlife.
In addition to working on adding interest above the soil, it is also important to focus on plant choices that will increase soil health. By installing plants with differing root depths, the structure and nutrient availability of soil can be boosted, which in turn affects what can be grown in the garden as well as the health of the soil biome.
Pile it Up
Having piles of debris around the garden can provide valuable habitats for wildlife, including snakes, rodents, and insects. Even the simple action of having your composting pile on your property can go a long way in bringing in the right beneficial insects to the space. The idea is, they come for the compost, and stay for the healthy soil and environment being cultivated in the space.
Having piles of debris around the garden can provide valuable habitats for wildlife, including snakes, rodents, and insects. Even the simple action of having your composting pile on your property can go a long way in bringing in the right beneficial insects to the space. The idea is, they come for the compost, and stay for the healthy soil and environment being cultivated in the space.
Add Interest
Maximize the number, shape, size, color, and seasonal interest of the plants in your space. This concept, in addition to being a foundational idea of landscape design, will also increase the attractiveness of your garden to wildlife. A truly biodiverse garden has a lot of different plants in it, installed in groups or scattered randomly across the landscape. Tracking the bloom time of the plants in your garden is the first step in creating a plan for multi-season interest. Adding interest to gardens can also refer to adding a variety of smells, as well. Humans are not alone in enjoying a good long sniff of a flower. Insects and animals are also drawn into gardens by fragrance. In fact, most butterflies and some other insects will find foodplants by smell, not sight, and will travel from garden to garden to locate the correct species.
Maximize the number, shape, size, color, and seasonal interest of the plants in your space. This concept, in addition to being a foundational idea of landscape design, will also increase the attractiveness of your garden to wildlife. A truly biodiverse garden has a lot of different plants in it, installed in groups or scattered randomly across the landscape. Tracking the bloom time of the plants in your garden is the first step in creating a plan for multi-season interest. Adding interest to gardens can also refer to adding a variety of smells, as well. Humans are not alone in enjoying a good long sniff of a flower. Insects and animals are also drawn into gardens by fragrance. In fact, most butterflies and some other insects will find foodplants by smell, not sight, and will travel from garden to garden to locate the correct species.
Grass is Whack
Manicured lawns are vast green wastelands as far as biodiversity is concerned. Mixing it up by adding groundcover plants, spreading flower varieties, and more diverse grass species are all great ideas for lawn replacements. If you're not ready to get rid of the lawn just yet, that's all right too. It's possible to have the best of both worlds - grass areas amongst other landscaped areas, or simply a smaller area of manicured grass are both ideal compromises.
Manicured lawns are vast green wastelands as far as biodiversity is concerned. Mixing it up by adding groundcover plants, spreading flower varieties, and more diverse grass species are all great ideas for lawn replacements. If you're not ready to get rid of the lawn just yet, that's all right too. It's possible to have the best of both worlds - grass areas amongst other landscaped areas, or simply a smaller area of manicured grass are both ideal compromises.
Go All Out
Adding extras like a pond, dry creek bed, waterfall, or other wildlife-assisting areas of the garden can bring an even more diverse group in to the landscape. Gardens are hosts for many animals, who are helped along by structures like nesting boxes, bee hotels, pollinator ponds, sun-bathing rocks, and shaded resting areas. Bird feeders are great additions, especially during winter months when food sources are scarce.
Adding extras like a pond, dry creek bed, waterfall, or other wildlife-assisting areas of the garden can bring an even more diverse group in to the landscape. Gardens are hosts for many animals, who are helped along by structures like nesting boxes, bee hotels, pollinator ponds, sun-bathing rocks, and shaded resting areas. Bird feeders are great additions, especially during winter months when food sources are scarce.
Seeing it All
The last creature to think about when planning a biodiversity garden is you. After all of this time and effort spent creating, you'll want to have an easy way to navigate through the different garden microclimates you'll be creating, and some quiet places to sit and witness the changes happening in your own backyard. Creating a pathway around the perimeter of the garden as well as through it, complete with seating areas is a fundamental step that is sometimes missed. Creating a backyard wildlife habitat offers a unique opportunity to connect with nature while beautifying your yard.
The last creature to think about when planning a biodiversity garden is you. After all of this time and effort spent creating, you'll want to have an easy way to navigate through the different garden microclimates you'll be creating, and some quiet places to sit and witness the changes happening in your own backyard. Creating a pathway around the perimeter of the garden as well as through it, complete with seating areas is a fundamental step that is sometimes missed. Creating a backyard wildlife habitat offers a unique opportunity to connect with nature while beautifying your yard.
homework
Identification activity - how to use bug guide
biodiversity in your garden (see what you can find) - take a pic and identify.
5 easy ways you could increase biodiversity in your garden
go out into your garden at different times of the day, and write down the wildlife that you can see or hear.
biodiversity in your garden (see what you can find) - take a pic and identify.
5 easy ways you could increase biodiversity in your garden
go out into your garden at different times of the day, and write down the wildlife that you can see or hear.