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Nope, Not Yet
April 15, 2013
Once again, the weather dominates.
The same system that brought feet of snow, freezing rain, floods and wind to the northern regions, also brought severe storms and tornadoes to the south.
Days of rain, wind and cold, with no sunshine made this past week a challenge for sure.
I can say the worm population is thriving and. the robins are gorging.
Water levels are high, and some local flooding is occurring.
We even had a duck swimming in a puddle (sorry no picture).
(part of my yard in standing water and floating mulch from last year).
Again, prayers go out to the many affected by the weather.
Bird migration continues.
This past week, Tree swallows arrived.
About a week later than years past.
While length of day is the major determining factor in migration (stirs the hormones).
Weather can and does play a role in when certain birds arrive.
It is a good thing that some species of birds are slow to arrive.
Species like swallows and warblers are insectivores.
Cold weather keeps insects in hibernation, or put the bugs in hiding.
Without insects, birds will die (it has happened before).
I was blessed with a new life list addition this past Wednesday.
For the first time, I saw and had a Fox sparrow in my yard (pictured).
By the actions, I first thought I had a weird looking Rufous-sided towhee.
You know, the hopping back and forth as the glean for food.
A second glance forced me to go to the book.
Fox sparrows nest in much of Canada, Alaska and the mountain states in the west.
They winter along the Pacific coast and much of the southern 2/3 of the United States.
You would think I would have seen one before now.
Anyway, it was nice to have a visitor, even if it was a short visit.
House Sparrows often give All Sparrows a bad reputation.
Our native sparrows are welcome birds and besides, House sparrows are part of the 'Finch Family', not sparrow family.
Dark-eyed juncos are still plentiful.
I have more of them now than in the dead of winter.
They must know the north country is still covered in white :-)
American goldfinches are looking more like goldies, even the black caps are visible (pictured below).
While friends in the deep south, southwest and Pacific coast area are busy with gardens, us northern folk are still thawing out, or drying out.
Way too cold or wet to plant anything, never mind working outside.
Still, garden plans and anticipation grow large.
Before you think about planting your shaded areas with impatiens, read below and
Impatiens aren't exactly about wildlife (other then pollinators).
Native to eastern Africa from Kenya to Mozambique, impatiens have found their way into Gardens around the globe.
The past couple of years have shown a devastating fungus to Impatiens throughout much of North America.
If you haven't read or heard about Impatiens Downy Mildew, you are now.
Sadly, many growers and sellers choose to not inform the public (customers).
Impatiens are a favorite garden flower, it thrives in shade where many blooming annuals cannot.
Lush beds attract pollinators and may offer protection for toads and fledged birds.
Before you go out and spend your hard earned money, read this bit of information.
I hope it is helpful.
Impatiens downy mildew is a destructive foliage disease of Impatiens walleriana.
Origination is believed to be Europe.
There have been reports of this disease in production greenhouses in the United States since 2004.
Widespread regional outbreaks of impatiens downy mildew were observed for the first time in North American landscapes in 2011.
By the end of the 2012 season, 'Impatiens Downy Mildew' had been confirmed in 33 states and parts of Quebec and Ontario, Canada.
(Last summer the fungus ravaged impatiens here in much of Michigan.)
About the only states not effected are the northern plains and mountain states
The incidence and distribution of this disease in North America may be even greater than realized due to unfamiliarity with the signs and symptoms of the disease.
Especially by gardeners and the home landscape.
Impatiens with downy mildew symptoms begin as a light-green yellowing or stippling of infected leaves.
Very subtle gray lines or markings are sometimes observed on the top of the leaf.
Infected leaves may curl downward at the edges, but generally this is a more advanced symptom of infection.
Young plants and immature plant tissues are especially susceptible to infection.
Leaf symptoms are often first observed on the younger growth.
Plants infected at an early stage of development may be stunted in both height and leaf size, yet may show no visible signs of sporulation (mildew) if conditions are not favorable for disease expression.
A white, downy-like growth composed of spores may be visible on the underside of infected leaves under cool temperatures (about 60 to 73 F/15 to 22 C) and moist or humid conditions.
When looking for signs, it is very important to turn leaves over to observe the undersides for this white growth.
The time from infection to the appearance of symptoms varies from about five to 14 days depending on the age of plant tissue, temperature and humidity.
The period between infection and visible plant symptoms is of concern because infected plants could potentially be shipped or moved without even knowing there is a disease problem.
As the disease continues to progress, eventually the leaves and flowers will drop, resulting in bare stems with only a few tiny, yellow leaves remaining.
This symptom is more likely to be observed in a landscape setting where symptoms and early signs of infection are more likely to go unnoticed.
In a a greenhouse setting where plants are frequently scouted and suspect plants would be quickly trashed.
LIFE CYCLE of the DISEASE:
The pathogen that causes downy mildew is a type of water mold and is classified as more closely related to algae than to fungi.
Downy mildew can spread by two different types of spores.
One type, zoospores, moves through water.
They are also easily windborne when contained in a larger structure called a sporangium.
This explains why this disease is spread by splashing overhead irrigation, rainfall and wind.
The other type of spores, (oospores), forms inside plant tissues where they can survive for years.
Downy mildew is very aggressive and can rapidly spread, so be sure to act quickly if you spot it.
This pathogen may erupt under high humidity, cool temperatures, and overcrowding.
Overcrowding reduces the wind movement between plants that helps dry leaves more quickly.
Prevention is the only effective management strategy.
Elimination of overhead and nighttime watering, excessive fertilization, overcrowded planting beds, and other stresses on the plants would all be very helpful in avoiding or reducing occurrence of this pathogen.
However, our desire for tightly arranged mass plantings in the landscape, irrigation systems, and periodic rainfall make this difficult to achieve.
Be sure to carefully inspect impatiens leaves and stems purchased for the landscape before they are installed to help ensure that affected plants are rejected.
Once in the landscape, the plants can be attacked by wind borne spores, but it is always better to avoid bringing the pathogen in on plant materials.
(Mildew on leaf underside)
Caused by The water mold Plasmopara obducens.
Hosts: All varieties of garden impatiens, Impatiens walleriana and balsam impatiens, Impatiens balsamina.
Wild jewelweeds are also susceptible.
Non-Hosts: New Guinea impatiens, Sunpatiens and other plants are NOT affected.
Symptoms: Yellowing of the upper leaf surface and downward curling foliage.
Early symptoms may resemble nutritional problems, but undersides of leaves are covered in a white fuzzy growth.
As the disease progresses leaves and flowers drop, leaving bare stems behind.
Eventually the entire plant collapses.
Spread: Spores in water splashed from nearby infected plants, spores blown long distances by the wind or spores that over wintered in the garden soil.
Movement of infected plant material also facilitates the spread of the disease.
Because Downy Mildew is an airborne pathogen, spreading by the wind, water, animals, birds and insects, as well as people, and remains viable in soils and plant materials for 3 to 5 years.
(I've read up to 8 years).
Environment: Cool-humid conditions.
Prevention: Avoid growing impatiens in environments where leaves stay wet for long periods of time such as in dense shade, or crowded plantings with poor air circulation.
Avoid overhead irrigation and water plants early in the day when foliage has plenty of time to dry before nightfall.
Inspect plants before you purchase.
Treatment: Infected plants will not recover.
Immediately remove plants with symptoms, including roots, bag and discard.
Do not compost plants with impatiens downy mildew.
Aggressive preventative fungicide programs can be employed in the greenhouse to prevent disease, and I am told preventive fungicide use will also help in gardens, if a solid program is followed.
Don't plant in the same spot as last year.
Alternative Plants: Substitutes for impatiens include begonias, coleus and New Guinea impatiens.
(New Guinea Impatiens)
Food for Thought:
If you experienced Downy Mildew last year, it is wise to forgo Impatiens walleriana for a few years.
Downy Mildew is an airborne pathogen, spreading by the wind, water, animals, birds and insects, as well as people, and remains viable in soils for 3 to 5 years. (I've read up to 8 years).
While breeders are collaborating to educate the industry and public about Impatiens Downy Mildew, they are also working individually to improve impatiens species genetically, culturally and aesthetically.
Don't be surprised if new fungicides come on the market in the next couple of years.
Shop at reputable nurseries and garden centers that will assure you of healthy and disease free plants .
While many growers and sellers are reputable, many are only looking to take your money and will not even mention the risk of 'Impatiens Downy Mildew'.
I wont be planting any impatiens in my yard for the next few years, that's for sure.
Well, it is time to fly for now.
Before I go, here is your positive thought for the week.
For man, as for flower and beast and bird, the supreme triumph is to be most vividly, most perfectly alive.
David Herbert Lawrence
Sometimes I must use the Bible verses more than once.
The thief comes only to steal and kill and destroy; I have come that they may have life, and have it to the full.
"Treat the earth well:
It was not given to you by your parents,
It was loaned to you by your children.
We do not inherit the Earth from our
Ancestors, we borrow it from our Children."
Ancient Indian Proverb
Your friend indeed,
Better yet, have them sign up so they can receive their own letters.
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