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Silver-Leaf Willow

shane - January 12, 2017 - A-Z Plant Maintenance, Trees

Salix alba sibirica

Silver leaf willow 2 years after planting. J. Evans photo.

Over the past few years, silver-leaf willow has become one of our favourite shade trees.  While there are a handful of excellent mature specimens in Red Deer, it is still a very uncommon tree in our area.  With the declining population of mature weeping and paper birch in Red Deer, due mostly to bronze birch borer, silver-leaf willow makes an excellent replacement tree.

Mature trees reach about 30′ in crown width and 30′ in height.  Expect a growth rate of 4′ per year in suitable growing conditions.  They are suitable for parks, acreages, and large front yards, taking up roughly the same amount of space as a mature weeping birch.  The leaves are an interesting silver-grey-green, and the mature canopy has a distinct weeping form.  We have not encountered any insect or disease problems on the young trees we’ve planted.  The form and distinct foliage colour add an interesting contrast within the urban forest, and we consider the species highly under-planted.

Exposure

Full sun

Pruning Time

Mid-summer through dormancy for structural pruning.  Anytime for deadwood removal.  As with most species, pruning is much easier, and better for the tree, when the leaves are off.

Pruning

Train as a central-leader standard with well-spaced scaffold limbs, and reduce or remove co-dominant leaders.  It is important to stake new trees for two seasons.  We’ve found that the growth rate is so vigorous, that potted trees require additional staking, otherwise they will take on a significant lean away from the prevailing wind.  Once the root system can support the crown, the stakes can be removed.  Structural pruning is required at least once per season on fast-growing willow.  We generally assess their structure in late June, and again in Fall.

Crown Reduction

Unsuitable.  Allow a 15′ radius around or future growth, when deciding where to place the tree.  Willow readily decays from large wounds.

 

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB.

 

 

 

Siberian Elm

shane - January 11, 2017 - A-Z Plant Maintenance, Trees

Ulmus pumila

Siberian elms in Red Deer, AB. S. LePage photo.

Siberian elms are long-lasting shade trees on the Prairies.  In my 1950’s neighbourhood, the streets are lined with them, and most of them appear healthy.

Beyond their shade-producing capability, I am not a fan of this species.  They are prolific seed producers and the seeds readily sprout all over the neighbourhood.  Many of the planted trees have long since died in neighbouring yards, but the progeny of the local street trees remain, often lurking at the corners of yards, behind a garage, or sharing the space with the trash can in the alley.  I respect Siberian elm like I respect dandelions and quack grass – for their survivability as a species.  From a horticultural perspective, I find them a nuisance.

They are messy, their wood is weak and rots easily, and they can be dangerous for an arborist to climb.  In Red Deer, they are prone to leafminer infestation each spring, which can render most of their foliage brown by late June.

On the flip side, they are resistant to Dutch elm disease and European elm scale, so we will likely see them outperform in places like Calgary or Lethbridge.

This is not a species I would consider planting in an average residential yard, but I would use them on acreages or as a shelter-belt tree.

Exposure

Full sun

Pruning Time

Whenever the chainsaw is sharp!  Actually, these trees should be pruned during the same as American elms, from Oct.1-Mar.31, to prevent the spread of Dutch elm disease.

Pruning

Train as a central-leader standard, with well-spaced scaffold limbs.  Subordinate co-dominant leaders.  New trees are best pruned annually so they develop a strong structure.  On mature specimens, remove dead, diseased, and storm-damaged branches.  Remove badly rubbing or crossing branches, if appropriate, but pay attention the size of cut you have to make, and the growth rate of the tree.  It isn’t worth it to take off a large branch, just for the sake of rubbing, if the large would will allow decay to form in the tree.  Siberian elms readily decay from wounds.  Reduce branches as necessary to clear structures, walkways, and driveways, as needed.

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB.

Sea Buckthorn

shane - January 11, 2017 - Uncategorized

Hippophae rhamnoides & cvs.

Sea buckthorn is a very common and well-respected plant in the eastern part of the world, where it’s used to produce around 200 different products.  The berries are high in Vitamin C and other nutrients.  In the West, it is largely unknown, except to horticulturists, a few specialty berry growers, and a few adventurous homeowners.  It isn’t a common ornamental plant, and rightly so, as it thorny, suckers freely, and tends to take over the area where it’s planted.

It is a useful plant for reclamation and soil improvement projects, as its roots have the ability to fix nitrogen from the atmosphere.

We tried using the thornless cultivar ‘Hikul’ in a couple of residential plantings, but were put off by the massive amount of suckering the following two years after.  I no longer use sea buckthorn in small residential plantings.  They would be useful in shelter-belt plantings, or on acreages where their spread is either desirable, or at least not problematic.  The berries are delicious and very nutritious.  The foliage is a nice silvery-green, which adds nice contrast in a landscape.

Exposure

Full sun

Pruning Time

Dormant period (late October to early April).  Anytime, if only minor pruning is required.

Pruning

On an acreage sitaution, I’d just let this plant do it’s thing. The width might need to be taken in from time to time to keep it in the desired area.  Be prepared for a thicket.  Wildlife likes it.

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service In., Red Deer, AB.

Scots Pine

shane - January 11, 2017 - A-Z Plant Maintenance, Trees

Pinus sylvestris & cvs.

Scots pine in Red Deer. S. LePage photo.

I’m a huge fan of all the pines, especially Scots.  I love the colour and texture of the bark, the random crooks and bends of the trunk, and the way the limbs hold their needles, giving the trees the look of an exotic, oriental garden tree.

We are fortunate in Red Deer to have a lot of green spaces in the older neighbourhoods, with a lot of Scots pines in large, mixed, woody planting.  They stand up well as a specimen or accent shade tree, but look equally natural and appealing in a grove or shelterbelt.  One of the nicest shelterbelts I’ve seen is on an acreage between Sylvan lake and Bentley, consisting entirely of mature Scots pines.

Scots pines are available in a range of cultivars, from dwarf, to columnar, to specialty forms.

Exposure

Full sun

Pruning Time

Pruning is rarely required, so long as the tree is placed properly at planting.  For deadwood removal and clearance pruning, anytime of year would be fine.

Pruning

Remove deadwood if desired.  Clear back branches from sidewalks and structures as required on mature trees.

‘Water’s’ Scots pine. S. LePage photo.

Crown Reduction

Scots pine is a good candidate for Niwaki, or specialty pruning.  It is slow-growing, so creating an interesting specialty form will take many years.

For a good introduction to specialty pine pruning, look for the book Niwaki, by Jake Hobson.

 

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB

Saskatoon

shane - January 11, 2017 - A-Z Plant Maintenance, Fruiting Shrubs, Shrubs

Amelanchier alnifolia & cvs.

Saskatoon is one of my favourite plants.  I have fond childhood memories of berry-picking with my mom, in the northern BC woods.  Besides bearing tasty fruit, saskatoon is a great ornamental plant, with beautiful white flowers in spring, and excellent fall colour.  The many available cultivars allow you to choose the form you want, from the 5′ tall ‘Regent’, to the common Saskatoon, to the ‘Standing Ovation’ variety, which grows to about 14′ tall in a columnar fashion.  We like the idea of using the columnar form as an alternative to the over-planted Swedish columnar aspen.

Saskatoon is a close relative to the serviceberry tree, but much hardier.

We like to use saskatoons in a mixed planting with other fruiting shrubs, to form small Prairie orchards that will fit into an average-sized residential yard.  Who doesn’t enjoy fresh fruit straight from the tree in summer?

Saskatoon is prone to several diseases, including leaf spot, rust fungus, cytospora canker, powdery mildew, and fireblight.  I’ve found that good plant stock, properly planted, and grown in fertile soil with enough water and adequate air flow, will prevent most incidences of disease.

Exposure

Full sun.

Pruning Time

Anytime if up to 10% of the canopy is to be pruned.  Otherwise, it is best to wait for the dormant season (late October – early April).  It is nice to prune these shrubs when the leaves are off, and you can see what you’re looking at.

Pruning

This somewhat depends on the variety, and the intended purpose of the shrub.  If saskatoon is planted in a grove on an acreage, I would say that less is more, and I would suggest simply deadwood pruning each year, and removing the odd major crossing/rubbing stem.  The same would go for an orchard-type planting, where the only pruning might be to reduce the width of the rows at some point.

More intensive pruning is necessary when the shrubs are place in ornamental shrub beds, or in mixed ornamental/fruit garden plantings, where a cleaner-looking specimen is more desirable.

I would prune common saskatoon in a similar manner as common lilac, or high-bush cranberry.  With the shorter cultivars, I would focus mainly on dead and diseased wood (important to keep the shrub disease-free), and remove redundant branches and badly crossing limbs.

We often get called in to prune saskatoon shrubs after they have been either brutally topped a few times, or neglected for many years.  At that point, the crowns grows like a bird’s nest, and attempting to undo that mess could result in a very leggy and flimsy plant.  With neglected specimens, I would advise staying out of the top of the crown, except to cut out disease.  Focus on the lower half of the plants, removing deadwood, and improving the overall shape of the clump of stems.  Of course, the best cure for neglect is not to look after your plants from the time of planting.

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB

Russian Olive

shane - January 11, 2017 - A-Z Plant Maintenance, Trees

Eleagnus angustifolia

Russian olive alongside a streambank.

Russian olive is not a common shade tree in my area.  It prefers poor soils and does well in waste places and less-than-ideal growing sites.  It has nice silvery-gray-green foliage, which makes an interesting accent in a mixed ornamental planting, or as a specimen in areas where other things won’t grow.  There is a planting a long Deerfoot Trail north in Calgary, on an inhospitable windy slope, that seems to be doing well.

The Russian olive tree tends to develop self-destructive branch structure if left to its own devices, so proper structural pruning is necessary for the first few years after planting.

I generally avoid planting this tree for four reasons:

1) In 2015, a reasearcher in Lacombe suggested that Russian olive be considered and invasive species that is likely to choke out streambank habitats.  I don’t want to contribute to that problem;

2) the trees are thorny and a nuisance to maintain;

3) they are prone to a fungal die-back disease that can result in disfigured, unattractive trees;

4) I prefer using silver-leaf willow, as the foliage is very similar, and the plant is less susceptible to disease.

The nicest Russian olive I ever saw was on a corner lot, on a busy road in Red Deer.  The owners removed the tree because a neighbour said it was too close to the foundation, which was nonsense.  The following year they planted a new Russian olive in the same spot!  Sometimes its best to call an arborist for advice.

Exposure

Full sun.

Pruning Time

Anytime of year for up to 10% pruning of canopy, or deadwood removal.  For heavy pruning, dormancy is best (late October until early April).

Pruning

If you have a chance to train this tree from planting, train as a central-leader standard, with well-spaced scaffold limbs.  I normally get called in to look after very mature and neglected specimens, where my options to improve branch structure are limited.  In that case, I remove dead, diseased, and damaged braches, reduce width and provide branch clearance over walkways and away from buildings, as required.

Crown Reduction

Generally, not suitable for crown reduction, and if planted in a suitable location, unnecessary.  I had one specimen in Leduc that we sheared by hand each year, at the request of the client.  It was a big, silvery ball, but not overly attractive.  She since removed the tree.  A well-structured, natural form is best for Russian olive.

 

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer.

Russian Almond

shane - January 9, 2017 - A-Z Plant Maintenance, Shrubs

Prunus tenella

Russian almond flowers.

Russian almond is uncommon in the Prairie landscape and is often mistaken for double-flowering plum.  Actually, it’s sometimes mis-labeled as a plum in the garden centres.  So I’ve had an occasional argument with people who want me to look at their plum, and when I tell them its an almond, they so, no it’s a plum, look at the tag.  Anyway, arguing is bad for business, so I say, well then, how would you like me to prune your plum.  Go with the flow, right?

The flowers are a vivid pink, and resemble the flowers of the muckle plum.  From my limited experience with this plant, I would suggest that if you plant one, give it some shelter from the prevailing wind, as it doesn’t appear to be as tough as our other Prunus varieties (ie. plums and cherries).

This is a compact shrub, probably to about 4′ by 4′.  It grows in a habit similar to nanking cherry, double flowering plum, and some shrub varieties of sour cherry.  We maintain them in the same way.

Exposure

Full sun.

Pruning Time

During the dormant season is best (after leaf drop until early April).

Pruning

Prune as you would a nanking cherry or sour cherry.  Russian almond sucker profusely, so the suckers will need to be thinned, similar to a forsythia, or lilac.

Crown Reduction

Not suitable for shearing.  Hedging this species would be appropriate in a zone that has a better growing season, like the Okanagan.  In the unlikely event that height needs to be reduced, use secateurs to reduce the height of individual branches.

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB

Rose

shane - January 9, 2017 - A-Z Plant Maintenance, Shrubs

Rose – Rosa cvs. and hybrids

Wild Rose – Rosa acicularis

Nearly Wild Rose (Rosa ‘Nearly Wild’). S. LePage photo.

Rose cultivation and maintenance is branch of horticulture unto itself, and I do not claim to be a rose expert, especially of the plethora of cultivars that are grown on the Prairies.  That said, basic rose maintenance is pretty straightforward.  For those of you who would like an excellent and very detailed book on advanced rose pruning and maintenance, find the book, Pruning & Training, by Brickell and Joyce, published by the Royal Horticultural Society in the UK, and by the American Horticultural Society in the US.

To keep roses looking their best in Alberta requires a lot of care, attention, and maintenance time.  Many of the varieties, despite being hardy, suffer from winter-kill, which necessitates frequent pruning.  Unless requested, I do not included roses in my landscape designs, and I do not plant them in my own yard, for a number of reasons:

 

  1. They tend to be a higher-maintenance plant and most people are looking for low-maintenance landscapes;
  2. Neglected specimens can turn into a wild bramble that, despite the pretty flower, becomes unsightly, especially in the dormant season;
  3. Because roses are so bright, showy, and dominant in the landscape, it is challenging to properly integrate them into mixed plantings, without having things look garish.  My analogy is this: they are like a boastful sports star – impossible to deny their abilities, but somewhat annoying to have around.
  4. While the above-ground parts might die-back, the roots of established plants are very tough, thus making it a challenge to get rid of established plants without a great deal of digging, or stump grinding.

So those are my cautionary comments.  Despite all that, I do love rose flowers, their shape, and particularly their scent.  If you don’t mind maintenance, enjoy gardening in general, and can find a spot in the garden where roses work, then give them a try.

My favourite rose is the wild rose, which has a delicate and fleeting pink flower, with an intoxicating fragrance.  They send out underground stems and are difficult to contain, hence their colonization of roadside ditches.  I found I was constantly tearing out roots to keep them in their spot.  Even with domestic varieties, it is tough to kill established plants.  I have one rose in my yard that came with the house when I bought it.  I cut it down to the ground in mid-summer a couple times, hoping that would kill it, but it persists.  I now treat it like a perennial.  I cut it back to the ground during the dormant season, and allow it to put out a few stems so that I have a few nice pink roses in mid-summer.  Maintaining it in this way keeps the plant small, and minimizes the amount of pruning, and prevents the plant from dominating the shrub bed.

There are a myriad of colours available in hardy roses.  From white to pinks, to reds and oranges and yellows.

Exposure

Full-sun.  Placed in part shade will slow their growth but still produce a decent flower display.

Pruning Time

This depends on your goals for the plant.  You can get away with one pruning per year, in the dormant season (November-early April), but if you want better flower production, less congested plants, and want to keep up with storm damage, deadheading, etc., you might have to prune your roses several times per season.

Basic Pruning

The most basic and effective way to prune roses is as follows:

  1. remove the oldest, thick, thorny stems each year;
  2. encourage the younger, more colourful stems;
  3. thin out the main stems by 1/3 or more so that the crown is well-spaced;
  4. cut back all the remaining stems by 1/2 to an outward facing bud.

Like I said, there are many ways to prune and train roses, but the above method is generally how we treat most roses we encounter in residential and commercial yards, unless otherwise specified by the customer.

Hedging and Shearing

I personally do not like the look of sheared roses as I think it makes them look butchered.  That said, I have seen a couple of interesting hedges of roses.  From a health perspective, they seem to tolerate shearing.  If you decide to plant a hedge of roses, and it turns out, please send me pictures.

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB

Oystershell Scale-Resistant Hedging Alternatives

shane - January 3, 2017 - A-Z Plant Maintenance, Hedges, Insect Pests

Oystershell scale continues to devastate Calgary hedges, and we treated a record number of them in 2016.  This trend is likely to continue.  It is getting to the point that keeping a cotoneaster healthy in Calgary might not be worth the money or effort for many people.  I’ve been telling my customers that I would come out with a list of hardy, insect and disease-resistant plants for hedging alternatives to cotoneaster.

So here it is.  I’ve chosen plants based on their reliability to over-winter without significant die-back.  The last thing you want in a hedge is for a large chunk of it to die-off due to winter-killed branches.  I’ve also chosen species that have something showy to offer, such as nice flowers, or brilliant fall colour.  Hedges are relatively high-maintenance, and I’ve indicated the level of maintenance required, and the best timing for pruning each plant.  I’ve listed a few of the pros and cons of each species as well, from my experience.

Happy hedging.  I welcome your comments and emails.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB.

Wolf Willow

shane - February 1, 2016 - A-Z Plant Maintenance, Shrubs, Uncategorized

Eleagnus commutata

Wolf-Willow-Image

Native to Alberta, wolf willow is a common site in natural areas such as streambanks, dry slopes, and open fields.  It is aggressive and often invasive, and I would not recommend planting this shrub in an ornamental setting.  It looks best in its native environment, on acreages, and in large, park-like settings.  It is an interesting contrast plant, with silvery foliage, yellow flowers, and a strong fragrance.

I rarely see this plant in the ornamental landscape.  It is used in reclamation and slope stabilization projects.

Exposure

Full sun.

Pruning Time

Anytime of year.

Pruning

Not normally necessary if used in a mass planting.  This plant spreads by suckering, so if used in an ornamental garden (not recommended) it would be necessary to control the suckers.

 

(c) 2016 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB