Lilly Pilly die back. Verticillium Wilt?

[Jackuza96]

Our Lilly Pilly trees started to drop leaves in November.

Leaves turned yellow and started to drop. Symptoms started with one of the trees then suddenly all the tree along the fence

started to show the same symptoms as if it was spreading.

During the winter time I water the trees once a months and let the rain water do the rest of the job.

Once the temperature started to rise I began deep watering twice a months plus rain water.

Gave some fertiliser(Dynamic lifter) to the trees in October and also gave Seasol liquid in September and October.

I dug up one of the trees to see the roots. Roots were moist and dark but did not have any rotting smell.

It didn't look or smell like a root rot so I increased the watering amount to the rest of the trees.

No signs of recovering. Only getting worse.

As I was pruning off the dead branches I've noticed dark marks in the stem. Could it be Verticillium Wilt??

Will they recover from current condition?

05 Nov leaves started to dropDie back from topLeaves easily come offRed Brown leavesChecking the rootsMoist but no Smell of rotting25 Nov all of the trees along the fence are like thisVerticillium Wilt??Verticillium Wilt??Verticillium Wilt?? Very dark.

[BradN]

Hi @Jackuza96, and welcome to the Bunnings Workshop community. It's great to have you here.

I'm sorry to see that you're having such trouble with your lilly pillies. Our Bunnings D.I.Y. expert @EricL will be back on the site later today, and in the meantime I'll also tag horticultural experts @Noelle and @Adam_W to see whether they can offer any advice.

I'm sure they'll find the photos you've supplied very helpful.

Is your soil very hard or compacted or full of clay? I'm intrigued by the shape of the rootbball of the plant that you've pulled out.

It looks as though the plant has had trouble putting out roots beyond the diameter of the pot that it came in or the hole it was planted in, and has mainly grown new roots through the very top of the soil. If it has been unable to develop a healthy rootball that might have contributed to its problems. Hopefully one of our more knowledgeable members can advise.

Brad

[EricL]

Hello @Jackuza96

Looking at the photos you posted, it looks like part of the roots are black but the outer roots look fine. Verticillium leaves a very recognizable mark on the inside of the stem of the tree and looking at those stems it might be just that.  I'm sorry to be the bearer of bad news, but there is no effective treatment for verticillium wilt. Your best course of action is to remove the infected tree, do not mix it in with your compost or use any part of it in your garden. It's best to put it in the bin so that the fungus does not spread further.

I suggest solarizing the infected area to reduce the amount of fungus in the soil. Unfortunately, there is no effective method of removing all the fungus in the soil. 

If you need further assistance, please let us know.

Eric

[Jackuza96]

Thanks for getting back to me.

Would you be able to recommend a type hedge or screen plants that are resistant to Verticillium Wilt? 

[EricL]

Hello @Jackuza96

Allow me to do a bit of investigation regarding what hedge is not susceptible to Verticillium Wilt. As soon as I have more information I'll get back to you.

Eric