Ferocactus sap

[spikef35]

The Sap of this ferocactus is Turing black along with the aerols are the aerols just going dormant or is it fungus

[iann]

Very common on Ferocactus. The "sap" is nectar exude presumably to attract insects. If it isn't eaten and doesn't dry out very quickly then it tends to turn black. This is sooty mould and is unsightly but not dangerous. You can see some here on a Glandulicactus.

wrightii-0721.jpg (99 KiB) Viewed 583 times

[DaveW]

As Ian says Sooty Mould that grows on the nectar from the extra floral nectaries of Ferocactus and related plants though unsightly is not harmful:-

http://www.cactusnursery.co.uk/sooty.htm" onclick="window.open(this.href);return false;

[spikef35]

Wow thanks but I must ask some of the aerols not the glands turned partly black is that a problem also is there any way to remove it. I might bring this one to my cactus and succulent show competition