Ecological Restoration
Everything wants to kill your native plants; part one.
It’s a tough world out there for young native plants. The environment, weather events, predators and weeds all want to kill them. Sometimes it may feel like an uphill battle keeping your new plants alive.
Let’s get straight into the thick of it with weeds. All weeds compete for resources (light, water, and nutrients) and grow many times faster than native trees. It’s important they are eliminated before planting to minimise their impact on native plants. Perennials and summer annual weeds pose the greatest risk to native plantings because they are not visible and have died back over winter when most restoration projects occur. Some harder-to-control weeds may require attention up to a year prior to planting. Tackling bindweed Great bindweed or convolvulus (part of the convolvulacae family) is a climbing, perennial weed that is common throughout New Zealand. It has recently received more attention because it is now becoming a significant weed in riparian plantings. What makes this weed so difficult to control is the extensive rhizome root system which can spread several metres underground. Bindweed competes for light, smothering and strangling young plants and taking over entire riparian margins. So, what can be done? Nonherbicide control options for bindweed may include mowing, grazing, cultivation, flooding, hand removal, light deprivation with plastic covers, mulch, or biological control. Unfortunately, all these methods are both time consuming and impractical in riparian margins and may not actually control great bindweed effectively. Chemical control is your best bet against this weed. In a study by Massey University on the effects of different herbicides on great bindweed, the following was found:
• No herbicide is known to control bindweed 100%. Translocating herbicides are most effective.
• Timing of spray applications is important. Late autumn application when sugars are being transported down into the roots is most effective.
• Follow up sprays are needed. Knock it while it’s down! Apply in early summer before sugar reserves are restored and the plant starts to translocate sugars to the roots.
• Application of Triclopyr/ picloram/aminopyralid (Brushkiller) and 2,4-D/ Dicamba are most effective.
When these chemicals were used in the trial, regrowth didn’t occur until 22 weeks after spraying. What else can be done? Plan and prepare! For a successful planting project, planning is just as important as choosing the right herbicide to use and the timing of the application. If you are planning a planting project and there is great bindweed or other pest species present, March is a great time to spray them out.
This article has been reproduced with the permission of Koroneiki Developments.
Planting services for riparian zones, revegetation and land stabilisation www.koroneiki.co.nz
Everything wants to kill your native plants; part two.
It’s a tough world out there for young native plants. The environment, weather events, predators and weeds all want to kill them. Sometimes it may feel like an uphill battle keeping your new plants alive. In this article we’ll discuss maintaining your plantings, the methods to use, and when to conduct maintenance and for how long.
What is maintenance and why is it important?
The maintenance of young native plants in the first two to three years of their life is often overlooked and can come back to bite you. Maintenance involves clearing or releasing the weeds and grasses from around the plant that are competing for light and nutrients. Releasing can be done through manual or chemical methods and this simple procedure is the most important thing you can do to ensure the best survival of your native plants. Maintenance may also involve controlling other weeds throughout the retired area or riparian margin, such as great bindweed, gorse, blackberry, woolly nightshade, honeysuckle and other common invasive weeds. Climbing weeds in particular can be an ongoing threat to plant survival.
How to perform maintenance.
Manual Releasing Manual releasing is performed by pulling out any weeds or grasses directly around the plant and they can be left to rot around the plant and act as mulch. Putting mats or mulch around each plant also slows down weeds, traps moisture and protects roots from frost. Use recycled biodegradable materials such as layers of newspaper, staked down cardboard, coconut mat, wool, or old wool carpets. Selective Herbicides Selective herbicides are one of the most effective ways to release native plants. The most common selective sprays used for releasing native plants are grass selective and broadleaf selective sprays. Grass selective sprays are very safe to use around most native plants, although care must be taken when spraying around flax, native grasses and sedges, cabbage tree and toe toe. Broadleaf sprays are safe to use around sedges, flax, and toe toe to control broadleaf weeds, but some care must be taken when used around other natives. Broad Spectrum Herbicides Native trees are very susceptible to broad spectrum herbicides such as glyphosate. When using broad spectrum sprays, you need to take care that the chemicals do not get on the plant. Using a spray guard to minimise wind drift is recommended. We use and recommend a combination of manual releasing combined with selective herbicides. This is both efficient and provides good results allowing the natives to thrive when they have no competition. Maintenance should be performed at least twice a year during spring and autumn when weeds and grasses are actively growing. Good things take time and putting the mahi on maintenance will pay dividends later on.
This article has been reproduced with the permission of Koroneiki Developments.
Planting services for riparian zones, revegetation and land stabilisation www.koroneiki.co.nz
Everything wants to kill your native plants; part three.
It’s a tough world out there for young native plants. The environment, weather events, predators and weeds all want to kill them. Sometimes it may feel like an uphill battle keeping your new plants alive. In this article we’re going to touch on weather events such as droughts and floods and learn the best tips for mitigating their impact on your natives.
We can’t control the weather, but we can control what species we include in the project and where we plant them to ensure the best outcome. Choosing the right species Consider the following when choosing what to plant in an area:
• North or south facing
• Flood prone or dry
• Steep or flat
• Soil conditions (clay, sandy, peat) .
You don’t order your fertiliser from a generic menu, you tailor it to what your farm needs. The same goes for planting natives, tailor your mix to your site and you will have great success. Get advice from experts in the field. Talk to your local nursery or search online for what to plant in your area.
Floods
To avoid losing plants in floods, determine how your waterway behaves in low, medium and full flows and at different times in winter. Avoid planting in the flood path as this can slow down the flow of water, increasing the risk of floods. Use plants that are well rooted and can survive many days under water. Suitable plants for flood zones: Grasses and sedges such as pukio and toetoe. Steep terrain and dry areas Steep sidelings are prone to drying out in summer. Plant a simple mix of species that are hardy with good root systems. Diversity can be added later once shade has been created from previous plantings. Suitable species for drier areas: Akeake, koromiko, ribbonwood, kanuka, manuka, kohuhu (all fast growing and hardy). Larger totara and rewarewa (open dry hillsides in full sun). Soil conditions Know your soils in the area you want to plant. Streambanks can dry out in summer and need dry and flood tolerant species. Clay soils can become waterlogged in winter and dry out in summer. Suitable species for stream banks: Toetoe and harakeke (Be mindful that harakeke has a shallow root system and can pose a flood risk if planted too close to stream banks.) Suitable species forwaterlogged soils: Mingimingi, harakeke, manuka, and cabbage tree. Suitable species for clay soils: Manuka, mahoe and mingimingi. We hope this gives you some insight into what to plant where. Whatever planting project you’re planning on doing this winter, make sure you have a plan and get advice if you come unstuck.
This article has been reproduced with the permission of Koroneiki Developments.
Planting services for riparian zones, revegetation and land stabilisation www.koroneiki.co.nz