Myrtle rust is a fungal disease affecting New Zealand’s native Myrtaceae family. More than 60 million Myrtaceae seeds have been collected for long term storage to future proof these plants from the diesease. Technical Threats Advisor Jacqui Bond has been working on the collection of seed from populations of 37 threatened species around the country.Continue Reading...
Archives For plants
What is so special about the red tussock on the Gouland Downs you might ask? Harry Broad, DOC writer in residence, explains why this “dull and boring” plant is worthy of admiration.Continue Reading...
Today’s photo is of New Zealand’s native kōtukutuku/tree fuchsia blooming in Catchpool Valley near Wellington.Continue Reading...
Taupo’s Summerset Retirement Village property team recently helped DOC collect seeds for a 50 year Landcare Research project.Continue Reading...
If you’re out in the bush this spring, look out for one of our most striking native plants, the critically endangered ngutukākā/kakabeak.Continue Reading...
A beautiful pink kakabeak/kowhai ngutukaka flower to celebrate the first week of spring!Continue Reading...
By Sarah Thorne, Awarua Wetlands Project Manager
It sounds like a bad joke. What is green, stringy and lurks at the bottom of Waituna Lagoon? The answer is Ruppia. Or it should be. But right now the future is not looking very green for this aquatic plant.
So what is Ruppia?
Ruppia is a green, salt tolerant aquatic plant that grows on the floor of Waituna Lagoon like a meadow of long wavy seagrass. It’s essential for a healthy lagoon and is the life support system for the lagoon.
Just like grass, its roots hold the sediment together. Its leaves use up nutrients and create oxygen and they also provide a home for fish and aquatic invertebrates to live. It is even a meal for some fish and wildlife.
Without Ruppia the water quality declines, animal numbers decrease and the lagoon could become dominated by algae. Put simply: healthy Ruppia means a healthy lagoon and healthy fish.
DOC has just received the latest annual monitoring report from NIWA, which describes the health of the ruppia beds in the Waituna lagoon. This year’s results recorded the lowest number of sites with Ruppia and a reduction of overall cover of Ruppia since annual monitoring began in 2009. One of the species—Ruppia megacarpa, was only found at one of the 48 monitoring sites. Nuisance algal species that cause algal blooms and could smother Ruppia plants were also recorded in the lagoon during the monitoring.
Why should we be worried?
We know that Ruppia is very sensitive to water levels, salty conditions during spring germination, nutrient loads (nitrogen and phosphorous) and water clarity. Even though some overseas species of Ruppia are marine species, ours are freshwater and estuarine species that are only tolerant of salty conditions as opposed to being salt lovers
It is hoped that under ideal conditions (high water levels and low salinity) Ruppia will flourish in the lagoon again.
DOC is working with locals and the Waituna Partners and Working Groups to help create the best conditions possible for Ruppia in the Waituna Lagoon.
A full copy of the report is available on the DOC website.