The Colorado fir can live up to 350 years. With their long needles you can easily distinguish them from other fir trees native to this country. But sometimes she gets sick or is attacked by pests
How do you recognize diseases in the Colorado fir?
Colorado fir diseases include yellow or brown needles, falling needles and webs. Common diseases include pine canker, pine needle rust and gray mold, while common pests include cinara bark lice, pine trunk lice, spider mites and black-spotted weevil. Prevention is essential through good care.
Signs of diseases and pests
Depending on the type and severity of the disease or pest infestation, there are different signs that you can use to assess the he alth of your Colorado fir. These include, among others:
- yellow needles
- brown needles
- dropping needles
- Webs
- white, yellow or orange colored spores
Common Colorado Fir Diseases
Colorado firs are not usually affected by disease. In rare cases, viral and fungal diseases can occur. For example, a resin flow indicates a viral disease. Yellow needles can indicate a fungal disease. These include, for example, pine cancer, pine needle rust and gray mold.
Identifying fir canker and gray mold
Fir canker causes needles that are bent and later turn yellow. They are shed in summer. You can recognize an infestation by gray mold, for example, by white spore heads on the undersides of the needles. In addition, gray-brown threads can often be seen.
Common pests
Pests occur more frequently than diseases on Colorado firs in this country. There is a wide range of pests. However, these trees are predominantly attacked by the following pests if the location, climate and care conditions are poor:
- Lice such as the Cinara bark lice (black in color, reminiscent of spiders) or the pine trunk louse
- Spider mites
- Black-spotted Wreath Weevil
The pests usually suck out the plant sap. The needles then turn yellowish until they fall off due to weakness. Regular checks for pest infestation and immediate intervention when found or with the help of soapy water can help.
Prevention of diseases and pests – avoid care errors
Diseases and pests usually only appear on weakened plants. To ensure that the Colorado fir remains vital and therefore robust, you should avoid care mistakes, water if necessary, do not fertilize too much, etc.
Pay particular attention to the following aspects when choosing a location and in care:
- acidic pH value
- Avoiding waterlogging
- water during dry times
- do not plant in a full sun spot
- do not over-fertilize
- fertilize with Epsom s alt if there is a nutrient deficiency
Tip
On this popular Christmas tree, the old needles naturally turn brown and fall off in late summer (normal sign of aging).