Life cycle
Behind the Pear grid hides a rust fungus with the scientific name Gymnosporangium sabinae. This fungus goes through two development phases on different trees. The Sade tree is one of the main hosts in whose wood the fungus spreads and lives for many years.
also read
- How to combat pear rust on juniper
- These diseases occur on the juniper
- Copper rock pear does not suffer from a pear grid
Every year in spring it develops orange-colored fruiting bodies, which shrink when it is dry and swell when the weather is damp. These spore beds develop spores that spread more than 500 meters with the wind. They infect the leaves of wild and cultivated pears.
Fight
Since 2010 there has been a fungicide that is used specifically against pear rust. However, the remedy for combating the fungal disease is intended on pear trees. If used immediately after the first symptoms, the universal fungus-free agent stops the spores from spreading further. The active ingredient has a depot effect, so that the effect lasts even after the injection.
Prevent
Regularly check juniper bushes for club-like thickenings that occur between March and April. The affected branches should be cut far back into the healthy wood. However, it is not certain that the fungus was completely removed. Its mycelium often extends deep into the wood without you noticing. Heavily infested shrubs should be removed completely to stop further spread.
If you have pear trees in your garden, you should pick off the infested leaves and dispose of them. Dead shoots are regularly removed. To promote the vitality of the trees, you can spray plant strengtheners regularly.
This strengthens the tree and pear:
- Nettle stock
- Horsetail extract
- organic-mineral PK fertilizer
Robust species
The varieties Juniperus sabina 'Blue Danube', 'Blue Haven' and 'Tamariscifolia' are particularly susceptible to rust fungus. Instead of the sedge tree, choose other types of juniper that are less susceptible to pear grate infestation.
Non-susceptible species and varieties:
- Juniperus horizontalis: 'Blue Chip' and 'Prince of Wales'
- Juniperus x pfitzeriana: 'Mint Julep' and 'Pfitzeriana Glauca'
- Juniperus squamata: 'Blue Carpet', 'Meyeri', 'Blue Star' and 'Holger'
