Grass Trees dying in Mid North Coast NSW
We live in Dunbogan on the Mid North Coast of NSW. We have several grass trees that have started to die over the past 12 to 24 months. Yet we have many more that are thriving as usual. We built our house (around and amongst the well established grass trees over 12 years ago) and for the first 10 years they have grown and continued to do so well. Then slowly about 10 of them have started to die. My husband is fairly knowledgeable in Indigenous plants and he can not work out why.
We have not done anything new near them or around them over the past 10 years either. We don’t fertilize, mulch or water them. We have just let them survive naturally as they had previously done. None of the other plants are dying, Banksia, gums and indigenous understory are all still thriving.
We have asked local wildlife nurseries in our region but they too cant understand why some are while others only meters away are all doing so well.
I have attached some photos of the dying ones and the ones only meters away that are still doing really well. Hoping someone cane help. Kingsley Dixon recommended I contact Brett Summerall whom I believe is part of the BGBN team? He believed his knowledge would be valuable in finding the answer. Thankyou all so much for ready this.
NetteWe are desperate to do what we need to help them survive …. which we may be told is nothing and they will do their thing, but we want to make sure that is the right direction to take.
Hi Nette,
Thank you for sending through your question!
We contacted Brett and he provided the following response:
The symptoms that are visible in your photos are certainly similar to the sorts of responses we see when Grass Trees are infected with Phytophthora cinnamomi. The collapse you can see in one of the plants is very much that type of symptom. We have had some grass trees with similar symptoms at the Royal Botanic Garden Sydney and we applied potassium phosphonate (Fosacid or Antirot are common trade names) at the recommended rates as a foliar spray (2 sprays at a 2-3 week interval) and have had a good recovery in our plants. This might be worth considering. This chemical is very safe to use and works to enhance the defence responses of the plants.
Kind regards,
Alex Lucchetti