Re: Banksia Serrata - Phytophthora Root Rot?
Posted: April 16th, 2023, 8:13 pm
Hi Shibui and Grant,
Thanks for replying.
Is it normal for the foliage to turn yellow and die off in such a quick, uniform manner (all foliage on one branch changed within 3-7 days, during a week of heavy rain; moving from bottom-up)?
- You can see the photos of the plant before the yellowing took over a week or two prior, in one of my replies.
Whilst some sources say foliage die-back is slow with phytophthora, others state it can happen almost overnight, particualrly in vulnerable shrubs or plants.
I hypothesised phytophpthoria for several reasons:
1) Its in a banksia
2) Changes occurred quickly after a week or two of heavy rains.
3) the foliage yellowing/die off was too rapid and uniform to be normal loss of foliage
3) the base of the pot was waterlogged, with compacted fine rotten medium (coco coir/pine mulch, i believe).
4) many of the roots at the bottom were a dark brown colour, and soft texture (see pictures)
You're right, there is no reason to suggest the mycelium I saw is phytophthoria - that is just my confirmation bias.
Thanks for replying.
Is it normal for the foliage to turn yellow and die off in such a quick, uniform manner (all foliage on one branch changed within 3-7 days, during a week of heavy rain; moving from bottom-up)?
- You can see the photos of the plant before the yellowing took over a week or two prior, in one of my replies.
Whilst some sources say foliage die-back is slow with phytophthora, others state it can happen almost overnight, particualrly in vulnerable shrubs or plants.
I hypothesised phytophpthoria for several reasons:
1) Its in a banksia
2) Changes occurred quickly after a week or two of heavy rains.
3) the foliage yellowing/die off was too rapid and uniform to be normal loss of foliage
3) the base of the pot was waterlogged, with compacted fine rotten medium (coco coir/pine mulch, i believe).
4) many of the roots at the bottom were a dark brown colour, and soft texture (see pictures)
You're right, there is no reason to suggest the mycelium I saw is phytophthoria - that is just my confirmation bias.