One measurement we use in helping to determine overall soil health is soil pH. This is a common concept and important to understand, but is only one of many measurements we use to determine overall soil health. A good soil health recommendation will take many factors into consideration, but soil pH is the starting point, as it helps us determine nutrient availability, the tightness of soils, and the ability of soil biology to thrive or not. The wrong pH may encourage fungal pathogens, while the proper soil pH range will encourage good soil microbes.
The pH scale runs from 0 to 14. Any pH reading below 7 is acidic and any pH above 7 is alkaline. A pH of 7 indicates a neutral soil. Most trees will grow in soils having a pH between 6.5 (slightly acid) and 7.2 (slightly alkaline). Ideally, maintaining a soil close to 6.8 is perfect for most trees. There are a few plants that prefer a soil pH below 6.0. These “acid-loving” plants include azaleas, rhododendrons, and blueberries. The soil pH for these plants can be lowered by incorporating elemental sulfur (S) into the soil. Since the soil acidifying response to elemental sulfur is slow, it should be applied and incorporated a year before planting.
Leaf scab diseases are a type of fungal infection that affect the leaves of apple, hawthorn and crabapple trees primarily. There is more than one fungal organism that creates this disease, but how they attack a tree and the treatments for them are very similar, so we will simplify the discussion by calling them leaf scab diseases.
Apples, crabapples, and hawthorn all can be affected by this disease, as well as some pear tree types. Out breaks are more severe after a wet, cool spring.
The fungus develops in the early Spring after spores are produced and distributed by wind and rain.
These spores infect newly forming leaves causing small brownish-green lesions on the young leaves. Once established on the new leaves, new spores are form and the process is repeated. As the disease develops on the leaves, the infected areas change colors and spread, until most of the leaf is affected and it falls off. Fruit can be affected too and even flowers may show symptoms. The fruit will become deformed and fall off prematurely.
Some varieties of flowering fruit trees are resistant and it is important when planting new ornamental hawthorn, crabapples or pear that you select the right varieties.
Older varieties are often most susceptible and need regular treatments to prevent early leaf fall. While it typically doesn’t kill the tree outright, the lack of leaves reduces the health and vigor of the tree and makes it more susceptible to other problems.
Arborwell has successful and cost-effective preventative programs available as well as “rescue” type programs that may be needed in certain situations.
Your Arborwell arborist can determine if this is a problem in your landscape and recommend an appropriate program for you.
Fill out the form below to set up a site inspection.
When sycamore trees fail to thrive, we often look at leaf diseases like anthracnose and powder mildew as the major culprits. While these diseases are easy to spot, there is an insect that is much harder to see that often times contributes to sycamore problems. Sycamore scale is a small (1/16”) scale that feeds mostly on leaf tissue. This reduces the vigor and overall health of the tree. When sycamores are weaker they tend to get leaf diseases worse, which continues the downhill spiral of tree health.
These tiny scale insects overwinter on the bark and in the duff below the tree, then move to the leaves during the early spring. As they establish on the leaves they begin feeding and reducing the ability of the tree to produce and store energy in the form of sugars. When they are quite established, you can often see little “pinpricks” on the leaves as you look through the canopy. Left untreated, the tree will slowly begin to decline.
While unchecked infestations of Sycamore scale typically do not kill a tree outright, the trees are weakened enough that other diseases more easily attack both the leaves and the twigs. Excessive leaf drop from leaf diseases and twig dieback from branch diseases can become problematic season after season.
A good program for preventing diseases, regular nutritional feeding and proper watering should also include insect prevention to keep these tiny scale insects from becoming a problem. If you are concerned about your sycamore trees your Arborwell arborist can inspect and develop a program that encourages a healthy tree and discourages insects pests like Sycamore scale.
Fill out the form below to set up a contact-free inspection.
This year’s mild winter and wet early spring has encouraged many insect pests so far this spring. One of the worst types are aphids, which seem to be abundant already. There are many types of aphids and they attack many of our most common and popular trees including: Crape myrtle, crabapple, birch, hackberry, hawthorn, maple, oak, strawberry tree, tulip tree and of course roses, too. Aphids produce an inordinate amount of a sticky liquid called honeydew. With the population of aphids so abundant so early in the season, it will be very important to protect trees soon if you have not done so already.
Slowing down aphid populations after they have become a messy problem is possible, but is usually more costly and usually involves washing off sidewalks or paved areas too. To protect your trees from aphids or other pests, fill out the form below to contact your Arborwell arborist for a comprehensive protection plan.
Many plants suffer or die in soil that is too wet or too dry. Knowing what type of soil you have and how it affects the greenery on your commercial property can dramatically impact your chances of successfully growing healthy, beautiful foliage. Your soil varies depending on your region and even how your property is situated. For example, hillside properties almost always drain well, while bottomland can be extremely poor in drainage. There is also diversity in soil structure that influences soil
drainage and plant health care needs.
How Your Soil Type Affects Your Plants and Trees
What do soil type and
drainage have to do with plant health care? As with the value of commercial
real estate, the key to plant health is often “location, location, location.” Soil drainage affects the availability of water and plant nutrients. Many commercial landscaping sites lack the ideal drainage conditions. Because each plant species has different nutrient and irrigation needs, understanding the soil type on your property can help you manage issues integral to plant health.
Common Soil Types
Do you know which of these common soil
types you have on your Seattle or Bay Area commercial property?
Sand Sand particles are quite large, draining quickly. Because sand does not retain moisture or nutrients well, plants grown in this type of soil require more frequent watering and intensive plant nutrient management to ensure health.
Clay Clay particles are extremely fine, sticking tightly together when moist. Clay is packed with nutrients and holds water well, but drains poorly, making your plants prone to fungal issues. If water displaces air, your plant’s roots, which thrive on oxygen, can suffocate, and they may die. Because of its dense composition, it can be difficult for the roots of young plants to penetrate clay.
Silty soil Typically found along riverbeds and lakes, silt particles are between sand and clay particles in size. Silty soil is one of the most fertile soil types, because it retains nutrients and moisture well but drains more quickly than clay.
Loam Loam is a mixture of sand, silt, and clay. Providing the benefits of all three types of soil, it is the ideal growing medium. Some loams possess a higher proportion of sand or clay by volume.
What Type of Soil Do You Have on Your Commercial Property?
The Bay Area is fortunate to have soil made of clay with loam, including rocky clay loam in the hills and gravelly loam in the valley.
Seattle Area soil is primarily Tokul soil, which is quite rare. Tokul soil began as volcanic ash. It is one of the most productive soils in the world. Tokul features a surface layer of gravelly loam, rich with plant matter, a reddish middle layer infused with iron oxides, and a cemented, root limiting layer of glacial till 20-40 inches below the soil surface. Though its top layers drain well, the cemented glacial till layer has high water and precipitation storage capabilities.
Finding the Right Balance
At Arborwell, we can help
you analyze your soil on your commercial property, identifying issues, and
taking corrective action when necessary. Depending on the unique composition of
your soil, we may need to employ solutions such as soil amendments, to correct
drainage and nutrient issues impacting plant health. Because each plant species
has different requirements, this can complicate the plant health care
landscape. Fortunately, Arborwell experts are well-versed on the soil types in
your region, expertly assessing the irrigation and nutrient needs of your
plants to help you achieve the right balance.
Flowering cherries are
one of the favorite sights in spring. the light pink or white flowers fill the
spring landscape and say goodbye to Winter and welcome to Spring. for most in
the Northwest west, it’s our favorite spring blooming tree.
One of the most serious problems that can affect flowering cherries and other flower fruit trees is a disease called Brown Rot Blossom Blight. This disease affects both the flower and the twig ends, leaving them brown and curled. These dead ends of the branches tend to hang on a long time so a severely affected tree looks quite distressed in the landscape. Unfortunately, this disease needs to be treated before flowers emerge in the spring, so being proactive is very important. We also know that soil conditions can play a big role in reducing Brown rot problems.
flowering cherries don’t look good, they have lots of dead tips and brown
flowers, is it dying?
It’s not dying, but it
probably has a serious disease that is important to treat before it spreads too
much. It is called Brown rot blossom blight and is common in the Pacific
Northwest and places that have moist spring times. Unfortunately, we can’t cure
the dead tips, but we can take steps to prevent the problem if we treat early
it spread to other trees, too?
Besides cherries, it
is common on flowering and fruiting peaches, plums, nectarines, and apricots.
In the worst springs, quince and a few other trees can get it too.
can it do about it now?
The best thing is to
prune back the dead twigs in the summer and remove any dead fruit that is on
the ground. Throw these pruning’s away, because they hold spores that can
re-infect next year.
do I prevent it next year?
We can treat your
trees before bloom season to reduce the number of infections and help the tree
combat the problem internally, without putting products in the air. But this
needs to happen before bloom season starts.
there organic or other solutions.
There are, but these
involve treatments on the tree itself. Timing is important though and it
usually takes several treatments to be successful. Also, we can look at the
soil conditions. When certain minerals are in short supply in the soil, they
can make your tree more susceptible to the disease. Proper pruning and the
right time and keeping your trees healthy can make a real difference too.
If you are concerned about Brown rot blossom blight on your trees, fill out the form below to contact your Arborwell arborist and schedule an inspection.
Spruce trees are one
of the most popular trees in the Pacific Northwest. Seeing conifer trees with
shades of green, gray and blue-green in the winter is refreshing and brightens
the otherwise dull winter. Spruce trees
are common to this area and very hardy trees. The blue spruce – native to
Colorado – is a favorite on public and private landscapes.
We do see a particular
problem on these trees that can cause the tree to decline fairly rapidly. The
spruce spider mite is a very fast reproducing insect that will quickly harm
spruce trees and most other conifers if not treated. They feed on the needles
and create a stippling effect, eventually turning the leave brown as they die
off. We are seeing more of this pest the last few seasons, so it is important
to pay closer attention to spruces, arborvitae and firs in particular.
Treatments done early can prevent damage most of the season, but if damage is noticed in the fall, it is important to treat quickly as that is when they do the most damage.
needles on my spruce tree are turning bronze colored and falling, what is
This is most likely
being caused by spruce spider mite, a fast reproducing insect that feeds on the
needles of spruce trees and other conifers. They feed by “rasping” the needle
with specialized mouth parts and the needle starts to turn yellowish, the
bronzy as it dies. When they turn bronze like that, it is a sign that you have
a fairly bad infestation. With spruce spider mite, you might also notice some
light webbing too.
my spruce be saved?
At this point, it is
imperative to treat quickly to with a fast-acting treatment to get the problem
under control. But yes, in most cases we can save the tree.
other trees do they affect?
They will feed on most
conifer trees, but mostly on spruce trees, fir trees, and arborvitae. They are
most active in the cool season, so damage is done in the spring and again the
fall. (Often the summer is when you notice the damage though because the
weakened tree has a harder time with the stress of summer heat.
When do I treat them?
When you see damage in
the summer or fall, it is important to treat them right away with a fast-acting
product. You should also avoid spraying products on the tree during this time,
because you will harm the predatory insects that feed on spider mites. Those
are the good guys we want to keep. In the fall or early spring, we can do a
proactive treatment that prevents the population from building up too high.
This allows the tree to recover more quickly. Without any treatments,
populations can build so high they may eventually kill the tree.
else should I know?
Spruce spider mites
are a cool season spider mite, but there are warm season mites that feed on
other tree types and do most of their damage in the summer. Your Arborwell
arborist knows what to look for and can help spot problems before they get too
bad. Remember too that keeping trees healthy helps prevent trees from becoming
stressed, which allows insects to attack trees more easily. Proper feeding and
proper watering will go a long way to reducing spider mite problems.
If you are concerned about spider mites on your Spruce (or other) trees, fill out the form below to contact your Arborwell arborist to help you solve this problem for you.
Hemlock trees are very
susceptible to a small white woolly looking insect called the Hemlock woolly
Adelgid. They can build populations up quickly and when they are very active in
a region, cause widespread death of hemlock trees when not treated. On Fir trees,
there is a related insect called the Balsam Woolly Adelgid that is found
largely on the trunk stems and small twigs, where they feed voraciously,
weakening the tree quickly.
somewhat problematic because of how waxy and woolly their outer “layer” is. We
often use alternate treatments besides spraying for them, which gets better
results and we don’t harm the good guys as much. Click here to see how
Arborwell can help to protect your Hemlocks and Fir trees from either of these problems.
Adelgids are making a comeback
One insect that is not
talked about much but can become very problematic is a tiny, fuzzy white insect
called Adelgid. They feed almost exclusively on conifers, but each type is
fairly limited in the number of different tree types it feeds on. They feed on
the sap and weaken the trees. When populations are high enough, they will
eventually kill the tree, especially on hemlocks.
Hemlock Woolly Adelgid
These feed on the needles and small twigs of hemlock tree, forming masses of white cottony spots on hemlocks. They are most prevalent on Eastern hemlock trees and are less of a problem on the Western varieties of this tree.
Pine Bark Adelgid
Most common on thin barked pine trees, they tend to cover the bark close to where branches extend from the trunk, but can fill the entire trunk when the population builds up, creating an almost snow-like affect on the trunk. These adelgids weaken the tree when present in large numbers, but are often not fatal, and they tend to favor stressed tress, so maintaining healthy pine trees goes a long way to keeping this insect in check.
Cooley Spruce Gall Adelgid
They are found on Colorado blue spruce, Douglas fir, and Englemann and Sitka spruce. They feed at the tips of small twigs and form a unique looking gall. Once they mature and leave, the gall turns brown and dies, leaving tips of the tree looking unsightly. Rarely do they need treatment, but can be warranted when the population is high.
Balsam Woolly Adelgid
This tiny sucking insect was introduced to North America from Europe. It is a serious pest of true firs in forests and landscape, and in Christmas tree production. Balsam woolly adelgid feeds on the stems of true firs. White or grayish cotton like masses of eggs or newly hatched purplish-black insects can be found on the twigs, branches, or trunk. Heavy adelgid infestations may cover the entire trunk. The feeding insects cause the tree to form swollen, knob like areas at nodes and tips of infested branches. Adelgid infestations weaken trees, cause foliage to become sparse, and can kill trees. This is a serious pest in the forest and common on most firs in landscaped areas, Balsam fir and subalpine fir are particularly susceptible. There are two to four generations per year. We can help you determine if adelgids are a problem on your hemlocks, pines, firs or other conifers.
Fill out the form below to Contact your Arborwell arborist and schedule an inspection.