NATURE PARK MANAGEMENT II

Natural resources are valued highly today. This fact has driven a rapid growth in nature based parks.

Nature parks are managed for conservation, tourism and environmental values. This course develops your knowledge, awareness and networking within this industry sector.

This course is a natural progression from Nature Park Management I, but can be taken in its own right. It concentrates more on indigenous plants and using them to create natural, balanced ecosystems. Learn to create nature trails, build rockeries and pathways, construct ponds and watercourses, design picnic grounds and animal enclosures, market a nature park, and lots more.

FLOWERING GRASSLANDS IN NATURAL LANDSCAPES

Until recent times, there was not a great deal of interest in native grasslands. They were simply areas of land that could be easily used for stock grazing and cleared for development. However it is now recognised that grasslands are, like all other types of ecosystems, important resources in the natural landscape.

The value of these areas is not only in the grass species. There are many other plants, including herbs and wildflowers, which occur naturally in grasslands. Losing the grasslands would pose a serious threat to the gene pools of many of these plants. In addition we would lose the opportunity to explore their economic potential.

Some of the economic and environmental uses of grasses, herbs and wildflowers includes: 

• Providing raw material for pharmaceuticals and other chemicals
• Providing horticulturally valuable ornamental plants
• Providing material for breeding agricultural crops
• Providing essential food and habitat for many species of wildlife

 

 

Sensitive management practices

Management practices can be carried out to maintain and maximise populations of indigenous species. This option really only works if the site is still dominated by native grasses, or at least NOT dominated by vigorous introduced grass species.

Grazing of native grasslands by sheep, cattle or other introduced animals can destroy natural ecosystems. In some instances however, controlled grazing may work in relative harmony with the natural ecology. Sensitive management may involve determining what stocking rates are tolerable, and not exceeding those rates.

Repeated burning, slashing or cultivation can reduce native plant populations in a grassland over time. Though these might be standard land management practices on some sites, they should not be undertaken on native grasslands unless the full implications of the procedure are first understood.

These practices are more likely to be a problem in native grasslands contaminated with weed species. The changes in the soil conditions will often create conditions less conducive to native species and more conducive to weed species. The net result can be that weeds develop a dominance.

In situations where taller exotic grasses are becoming dominant, appropriate management may be to mow the grasses low (eg. 5-10cm) to weaken them, and allow resilient native herbs to compete more with the grasses. (This should be done in late winter, just before a flush of growth in the native species.)

 

Reintroduction of Native Species

Indigenous species can be introduced into either exotic or native grasslands. This may be done by:

Surface Sowing

The area is first mown low or burnt to increase the chances of broadcast seed reaching the soil and remaining moist while germinating. In the past, the results of this procedure have been poor, but it can work especially if a light mulch is used after the seed is sown.

Slit Seeding

This involves planting seed of native species into the soil in slits or rows; either by hand, or using a seed drill (i.e. seed sowing machine as used by farmers).

Planting Seedlings

Seedlings are raised in a nursery, then planted out. Timing is critical, depending on weather patterns and the species; climatic requirements.

 

Re-creation of Native Grasslands

Native grassland can be re-established on a changed, destroyed or degraded site. This is much easier in the absence of weed competition; weed control therefore is critical. Timing is also important if seeding into the field (ie. on the permanent site). You must also know and consider the germination requirements of any plants which are seeded (grasses, herbs, wildflowers etc). Some may require particular light, temperature or moisture conditions to germinate.

Growing Australian Native Plants in a Nature Park

The golden rule for growing natives is to select plants that have a record of doing well in your area. If you are in doubt, seek the advice of your local nursery and talk to fellow native plant lovers. But don’t forget that any plant in a garden needs some on-going care to give you its best – you can’t just plant and turn your back!

 

The following points are general comments about natives and shouldn’t be considered iron-clad rules:

• Don’t feed natives with fertilizers which contain a high percentage of phosphorus (including superphosphate).
• “Advanced” native trees and shrubs often don’t transplant well. Smaller plant specimens are not only cheaper; they are much more likely to succeed.
• Many natives require good drainage. It is often a good idea to plant them on a raised mound of soil.
• Mulching is generally desirable to keep roots cool and minimize water loss in summer
• A camellia may live for centuries, a rosebush for fifty years, but many of the most desirable natives are relatively short-lived. If you have a ten year old acacia or grevillea that is looking miserable, chances are that it is just suffering from old age. Harden your heart, remove the plant and replace it.

There are three main things which affect the way a plant grows. They are:

• Environmental factors such as temperature, light or moisture.
• Nutrition (i.e. the supply of nutrients to the plant).
• The influence of pest and diseases on the plant’s health

An understanding of how these three factors affect plant growth will improve your ability to make decisions about how to grow a particular plant in a particular place.

ENVIRONMENTAL FACTORS
Consider where the plant grows naturally. This will give you some idea of its requirements. For example, most banksias tend to occur in well-drained soils, indicating that they need good drainage; while plants which grow above the snowline will tolerate very cold conditions.
A plant which is grown outside of its natural environment can often still be grown successfully, but you may find that it will grow differently, for example tropical plants which are grown in the southern states tend to be smaller in size and may need more protection than they do in tropical areas.
Growth characteristics such as foliage colour, flowering, fruiting, and the rate of growth are largely controlled by temperature and light conditions. All plants have optimum, tolerable and intolerable temperature ranges. For instance, for a particular grevillea, optimum growth may be achieved if temperatures stay between 200Cand 300C. The same plant may tolerate temperatures as low as minus 50C and perhaps as high as 500C, but above or below these extremes the plant will die.
Many plants will lose the brilliant colour in their leaves if they do not get ample light. Flowering and subsequent fruit development will also be affected by low light levels for many plants.
Similarly, rainfall, wind, hail and frost will all affect plant growth.

NUTRITION
Both northern and southern rainforest species tend to require reasonably fertile soil conditions.

A large number of sclerophyll plants have evolved in relatively infertile soil conditions. Many of these plants will grow better in soil which is not overly fertile with many plants in the Proteaceae family in particular, prefer soils low in phosphorus.

SOILS AND PLANTS

Soil is important to the plant in providing the following:

Different soils have different characteristics with respect to the above factors. For example, a sandy soil provides less support than a clay soil, although fast growing plants often fall over in heavy clay soils, due to poor root penetration from a pot-pound root system. A clay soil provides less air, but a greater capacity to hold water than sand. A soil high in organic matter has a good ability to hold water, but doesn’t always provide good support and so on.

Improving Soils
While many native plants are hardy and adaptable with regard to the soil conditions in which they grow, most will benefit if a little effort is taken to improve the soil, in particular prior to planting.

Common Soil Problems

 

Poor soil structure.
Usually heavy soils, like pottery clay, which do not have the desirable crumbly structure; the crumbly structure means that there are pores between the crumbs, which allow air, water and roots through easily. Soils with poor structure do not allow water in easily, but when enough water gets through, they become waterlogged. Compaction by people, pets or heavy machinery makes these problems worse.

Poor drainage.
This is often a problem in areas with soils high in clay content. The problem is often due to poor soil structure, impervious layers in the soil or low lying areas.

Poor water retention.
In some soils, particularly sandy ones, drainage is excellent, but moisture retention can be a major problem.

Low fertility.
Many Australian soils, in particularly sandy ones, have low levels of fertility. Many ancient soils (eg. much of Austrakia), are low in phosphorus.

Salinity.
Occurs inland due to tree clearing and irrigation; in coastal areas it is caused by salt-laden winds.

Wrong pH.
Calcareous (alkaline) soils in some coastal and limestone areas, acid in agricultural areas or high organic soils. Acid soils are commonly associated with high rainfall and leaching (draining) of alkaline materials, while low rainfall areas are usually alkaline. Most natives prefer mildly acid to neutral soils, pH 5.5 to 7.

Non-wetting soils
Some soils contain lipid compounds from plants (eg oils) which repel rather than absorbing water. .