Brown Lacewings (Hemerobius spp.) As a Natural Pesticide
Terrie Greco, B.A.; HLT Dip.
Gardeners may not be as familiar with the Brown Lacewing as they are the Green Lacewing (which is a much prettier color). As it happens, the Brown Lacewing is right up at the top of the list of effective garden predators. Both the adult and larva has a voracious appetite for aphids, mites, thrips, mealy bug and other soft bodied insects. They are most active after dusk, hiding themselves in plant vegetation during the daylight hours – so it is no wonder we don’t see them around.
With a long life span and great reproductive capability they are considered to have excellent potential for biological pest control. Occurring naturally in arboreal forests and orchards, they have a capacity to tolerate a wide range of temperatures – making them a useful biological agent for pest control in temperate as well as tropical climates and greenhouses.
It goes without saying that their drab colour helps to provide camouflage – but did you know that sometimes the larva will also carry debris around on their backs to disguise themselves? The larva look like tiny alligators, and tend to swing their heads slightly from side to side when they are walking – so you see – they know how to strut their stuff! (Seriously – they are just on the lookout for food). Aren’t you glad they’re on our side?
Hemerobius spp. - Brown Lacewing Adult
This link has some great photos of the Brown Lacewing in all of its life stages.
http://www.ipm.ucdavis.edu/PMG/NE/brown_lacewing.html
And guess what! Biofloris carries these predators:
http://www.biofloris.com/beneficial-insects/brown-lacewing-adults-general-predator.html
The Praying Mantis As A Natural Pesticide
Terrie Greco, B.A.; HLT Dip.
The praying mantis is a Kung Fu King – really! Many martial arts have based defensive strike positions on the stance of the praying mantis.
Although there are many different species worldwide, one of the most familiar to gardeners is Mantis religiosa – or the European Praying Mantis.
Gardeners purchase this predatory insect in the egg state, or ‘ootheca’ and attach the egg casings to branches and twigs in the spring. It takes a few weeks of warm weather before the tiny mantis nymphs emerge – then watch out – they’ll be on the prowl.
Mantises are ‘ambush predators’ – they lie in wait for prey and strike with lightening speed. With the ability to camouflage themselves by appearing as part of a branch, twig or leaf, most unsuspecting prey does not have a chance of survival if they land near a mantis. The mantis holds their prey securely with their two front legs, which are equipped with razor sharp spines. Next, the mantis will bite the neck of their prey, paralyzing them. And yes, they usually start to eat them when they are still alive.
Mantises are true predatory insects – so they will control numerous pests – and the odd non- pest as well. Predators cannot distinguish between pest and beneficial insect. Why would you use them in the garden then? If your garden is experiencing problems with many different pest species, this generalist predator will keep pest populations at a manageable level.
Mantis religiosa - European Praying Mantis adult stage
Mantis religiosa – European Praying Mantis adult stage. The Praying Mantis predator uses its powerful front legs to strike with lightening speed. Image courtesy of: Joseph Berger, www.bugwood.org
Here is an interesting link from Animal Planet in which you can see predatory insects in action:
http://animal.discovery.com/videos/natures-perfect-predators-praying-mantis.html
Ladybugs as pesticides
Terrie Greco, B.A.; HLT Dip.
Following our recent blog on beneficial insects, we received several inquiries as to when is the best time to apply convergent ladybugs in the garden to fight pest insects. Well, that time happens to be now, mid July. We therefore recommend that you re-read or read the blog biofloris posted on the subject last year: Ladybugs gardeners’ best friends
Remember, please write if you have any questions or comments.
Using Phenology To Predict Pest Emergence
Terrie Greco, B.A.; HLT Dip.
Phenology? What on earth does that mean? Well, and very simply put, it is the science of making associations with certain stages of plant development with the timing of pest emergence. Climatic variables such as temperature, moisture and day length all play a part in when a plant will break bud and bloom – we can co-relate the hatching of insect eggs, for example – with the bud break or blooming of an ‘indicator’ plant. Good indicator plants are ones in which they are common to a large geographical area (a province or state), are easy to grow and have a short but well defined period of bloom. Gardeners can use indicator plants to predict pest emergence and plan effective treatment at the correct stage. A monthly calendar is not an accurate predictor for plant bloom times. For example, unseasonably warm or cool temperatures in the spring can advance or delay plant flowering. As it says on the USA National Phenology Network (USA-NPN) website: ‘Phenology, put another way, is simply nature’s calendar’. Well said! Here is the link for this website where you can find all sorts of fascinating information and opportunities to become an observer in your area.
Interestingly enough, the plant indicator in bloom may not even be a host for the pest we are watching for– but it has the same climatic requirements to emerge from a life cycle stage as the plant does to bloom.
Example – in Ontario and Quebec – when Saucer Magnolias (Magnolia soulangiana) are in the pink bud stage …. Cooley and Eastern Spruce Gall Adelgids should be treated with natural insecticides. Note that these aphid like-insects do not harm Magnolia, only certain Spruce species and Douglas Fir.
Example – in Ontario and Quebec – when Serviceberry (Amelanchier spp.) is in bloom – Gypsy Moth eggs will begin to hatch
Get the picture? Regardless of where you live in North America, you can find a phenology calendar or publication from your local horticultural or agricultural extension office that can help you accurately predict pest emergence. It’s really the coolest thing to know.
Here are a couple of pictures and links to explain further.
Image 1 – Magnolia soulangiana – Saucer Magnolia in bloom
Image 1 – Magnolia soulangiana – When the Saucer Magnolia is in bloom, gardeners should be checking conifers for Cooley and Eastern Spruce Gall Adelgids.
Magnolia image provided by www.permed.com/…/Magnolia_soulangiana_tree.jpg
For more information and images the Cooley and Eastern Spruce Gall Adelgids, check out the following two links:
http://www.for.gov.bc.ca/hfp/publications/00198/Cooley_spruce_gall_adelgid.htm
http://www.forestry.ubc.ca/fetch21/FRST308/lab4/adelges_abietis/spruce.html
Image 2 - Amelanchier canadensis, Serviceberry in spring bloom
Image 2 – Amelanchier canadensis When the Serviceberry is in spring bloom, gardeners should be watching for the emergence of Gypsy Moth Caterpillars on various tree species. Serviceberry image from the University of Delaware Cooperative Extension, Kent Co.
For information on the Gypsy Moth, check out the following link:
Caterpillar Pictures
Terrie Greco, B.A.; HLT Dip.
I got a lot of positive feedback on last week’s “Caterpillar Brigade” post. I also received numerous emails requesting photographs. So I put some together here for you:
Image 1 – Malacosoma americanum: Eastern Tent Caterpillar ‘tent’ Webs
Note that the Eastern Tent Caterpillar always produces a silken web in the forks of tree branches. During the day, the caterpillar leaves the nest to feed and returns at night. The nests grow larger as the caterpillars mature and need more room. Constant home renovation!
Photo courtesy of John Himmelman, childrens author, illustrator and naturalist
Image 2 – Malacosoma americanum: Eastern Tent Caterpillar Egg Bands
Note that compared to the Forest Tent Caterpillar egg bands, the edges are more rounded.
Photo courtesy of Brian Kunkel, University of Delaware, www.bugwood.org
Image 3 – Malacosoma americanum: Eastern Tent Caterpillar Mature Larva
Note that the Eastern Tent Caterpillar has a white stripe down the back, blue spots on either side and plenty of hairs (setae).
Photo courtesy of David Cappaert, Michigan State University, www.bugwood.org
Image 4 – Malacosoma americanum: Eastern Tent Caterpillar Adult Moth
Note the white forewing stripes on Estern Tent Caterpillar compared to the darkish stripes on Forest Tent Caterpillar. The adult female of the Eastern Tent lays eggs in early to mid summer in a band around twigs. The eggs over winter and hatch in early spring just before bud burst. This pest prefers apples, crabapples and cherry trees.
Photo courtesy of John Himmelman, author, illustrator and naturalist
Image 5 – Malacosoma disstria: Forest Tent Caterpillar egg band on twig. Pruning off the egg bands in spring will do much to reduce the population. Compared to Eastern Tent Caterpillar egg bands, the edges of the egg band is square rather than rounded.
Photo courtesy of Thérèse Arcand, Natural Resources Canada, Canadian Forest Service
Image 6 – Malacosoma disstria: Forest Tent Caterpillar mature larva – This caterpillar can be identified by the white ‘keyhole’ or ‘footprint’ shaped spots down the back and a blue stripe on either side of the body.
Photo courtesy of John Himmelman, author, illustrator and naturalist
Image 7 – Malacosoma disstria: Forest Tent Caterpillar Female Adult – The adult female moth lays hundreds of eggs on a small band around tree twigs in mid-summer. The eggs over winter and hatch in the spring. Note the dark beige coloured wings with the two dark downward facingbands on the forewings.
Photo courtesy of John Himmelman , author, illustrator and naturalist
Image 8 – Hyphantria cunea: Fall Webworm Tents – Compared to the webs of the Eastern Tent Caterpillar, which are produced in the forks of trees, Fall Webworm forms silken tents at the ends of branches. The larva feeds inside the tent, destroying all the foliage in the web before moving to another location on the tree.
Photo courtesy of G. Keith Douce, University of Georgia, www.bugwood.org
Image 9 – Hyphantria cunea: Fall Webworm Larva – The larva are creamy white with prominent black bumps on the body, and extremely hairy. If I were a bird – I would have trouble swallowing this caterpillar!
Photo courtesy of John Himmelman , author, illustrator and naturalist
Image 10 – Hyphantria cunea: Fall Webworm Adult Laying Eggs – The adult female lays a large mass of eggs on the underside of leaves of White Ash, Birch, Willow – to name just a few hosts. The egg masses can easily be missed by a homeowner. The adult is either pure white or has a scattering of small brownish/black markings on the white wings.
Photo courtesy of H C Ellis, University of Georgia, www.bugwood.org
Image 11 – Hyphantria cunea: Fall Webworm Adult –Portrait of a moth…you gotta love that face – and wait – is that hairstyle a mullet??? Joking aside – it’s an amazing photo of a moment in nature captured in time…
Photo courtesy of John Himmelman , author, illustrator and naturalist
We are very grateful to John Himmelman for generously offering permission for the use of his moth photographs on our website. John is a well known childrens author, illustrator and naturalist. Check out his websites below!
The Caterpillar Brigade
Terrie Greco, B.A.; HLT Dip.
When I was a child I found great pleasure in holding what I considered to be a fragile yet comical creature in my hand – the caterpillar. Over the years, I came to realize that caterpillars are programmed for plant destruction. It’s a survival strategy to which allows them to develop into the adult stage as a moth or butterfly and reproduce.
The caterpillars I find most intriguing are categorized as ‘the social caterpillars’ – (see link below for an explanation). They are the:
- Eastern Tent Caterpillar Malacosoma americanum
- Forest Tent Caterpillar Malacosoma disstria
- Fall Webworm Caterpillar Hyphantria cunea
Both Eastern and Forest Tent caterpillars emerge mid-late May from over wintering egg masses found on twigs. Eastern Tent caterpillars will attack crabapples, apples, and cherry trees. Forest Tent caterpillar prefers maples, oaks and birch as host plants. Fall Webworm larva emerge in late August from eggs laid on the undersides of leaves – this pest infests numerous fruit tree species along with elm and willow species.
Defoliation can be severe, and if repeated, can result in the death of the tree. Treatment with Bt (Bacillus thuringiensis) – a natural and safe bacterium – is the best known solution. It has proven over the years to be user-friendly, efficient and safe. One important thing: Bt is much more effective when the larva is small.
Why is Bt more effective on younger larva?
- Bt bacterium produces a crystalline protein toxin that kills the single layer of cells lining a caterpillar gut
- Cells in the younger larva are not multiplying and dividing as rapidly as in older larva – therefore the older larva can effectively ‘heal’ the gut wall and survive the effects of Bt. COOL!
- If Bt has not been effective for you in the past – you probably applied it too late!
Pruning out egg masses and opening webs to natural predators are easy ways to check an infestation before it’s too late – remember folks – effective treatment means catching things early!
This link describes the safety of the product Bt.
http://www.youtube.com/watch?v=7TTS80xyw4A
Excellent instructions and information on the use and application of Bt(Bacillus thuringiensis)
http://www.agf.gov.bc.ca/pesticides/infosheets/bt.pdf
Oh, and don’t forget to check out the following Web site for more info: http://www.bugwood.org/
Don’t ‘Cry Uncle’ if you have Ants!
Terrie Greco, B.A.; HLT Dip.
Many species of ants contribute to the ecology of the landscape, though there are times when we wish we could banish them from the home and garden. But you have to admire the work ethic of these ‘system engineers’.
The most common ants found on properties are small pavement and odorous ants. They are fairly easy to control using residual Pyrethrin sprays or Borax based baits. As a socially organized colony, the workers are really the only ones that enter the home foraging for food. The Queen hides deep in the nest – doing what Queen’s do best -wearing nice hats and waving to the masses. Seriously now…
Ants enter through cracks and crevices and are looking for a food source. Common sense dictates that if you see ants around baseboards (they usually create a path in straight lines) or on counters – you need to repair any openings around foundations and doorways. Protect food in airtight containers, wipe counters and baseboards with common vinegar (to disrupt pheromone trails) and practice good housekeeping – these simple habits will repel and minimize ants in the home.
In the garden, ants have a mutualistic relationship with aphids. Aphids produce a sticky sweet substance called honeydew which is a great food source for ant colonies. Ants protect, defend and transport wingless aphids in return for the privilege of ‘herding’ and ‘milking’ aphids for the rich honeydew.
Controlling ant’s outdoors requires patience and observation – make note of the ant pathways back to the nest and use diatomaceous earth or borax baits along the trails.
Take a look at the photos and links to learn more about the many species of ants, their odd behaviours, their relationships with other insects and natural control. They are a fascinating and complex creature. By the way, thank you to Alex Wild, a biologist at the University of Illinois for letting me reproduce these pictures here on the Biofloris blog. To see many other insect photos, check out his website at: http://www.alexanderwild.com/
Tetramorium caespitum - The Pavement Ant is a common household pest in many parts of North America. Photo courtesy of Alex Wild, http://www.alexanderwild.com/
Tapinoma sessile – The Odorous House Ant has a distinct smell when crushed – some say like rotten coconut! Photo courtesy of Alex Wild, http://www.alexanderwild.com/
References:
- A great list of different types of ants from the University of Minnesota
http://www.extension.umn.edu/distribution/housingandclothing/m1166.html
- A wonderful video called Lord of the Ants, narrated by Harrison Ford with Edward O. Wilson, a world renowned naturalist.
http://video.pbs.org/video/980049632/
- An ant game – match a species of ant with their peculiar behaviour
http://www.pbs.org/wgbh/nova/eowilson/game.html
- A fascinating article on the relationship between ants and aphids from Science Daily
http://www.sciencedaily.com/releases/2007/10/071009212548.htm
- Excellent reference info from Wikipedia
http://en.wikipedia.org/wiki/Pavement_ant
http://en.wikipedia.org/wiki/Tapinoma_sessile
- How to make Borax Ant Bait
http://www.ehow.com/how_4881566_make-borax-ant-bait.html
That Darn Lily Leaf Beetle!
Terrie Greco, B.A.; HLT Dip.
We have an intruder in this country – a bold, brash, bright reddish orange beetle known as the Lily Leaf Beetle (Lilioceris lilii). This beetle hails from Europe and Asia, and was noticed in the Montreal area in the early 1940’s. It has been heading west ever since, leaving a trail of destruction among your favourite Lily plants.
Even if this ‘import’ had natural predators, its habits are so disgusting that even the most self respecting bird avoids it. The larva has a peculiar habit of using its own excrement as a protective cloak. Not an attractive appetizer let alone a main course for any predator. If this wasn’t bad enough, the brightly coloured adult has an uncanny sense of timing. When the adult senses danger, (such as a gardener preparing to pluck it from the leaf) it folds up its six black legs and ‘sky dives’ to the ground – with its black underside facing up. Adventure and camouflage all in one clever ploy!
The burning question – how do we control it? Using Neem oil as a repellent on the leaves shows plenty of promise. Monitoring and handpicking are very effective. Watch for the brightly coloured adults emerging from the soil in late spring and grab them before they find true love! Each female can deposit 400+ eggs – capturing and destroying a few will make a difference. If some beetles end up having a tryst – don’t call yourself gram or gramps yet! Brush off small orange rows of eggs from the underside of leaves before the larval stage emerges. Two or more generations are possible, so be diligent with these recommendations until late August.
Check out the following photographs.
Lily Leaf Beetle .Note the bright red orange body and black head and legs – capture and destroy!!!
Lily Leaf Beetle. Adult females lay small orange cylindrical shaped eggs in neat rows on the underside of Lily leaves in late spring – brush them off with a gloved hand or remove the leaf.
Lily Leaf Beetle larva covered in an ‘excrement cloak’ – gross! Some insects have no manners…
Lily Leaf Beetle. I have removed these leaves to show the eggs and different stages of the larva. Notice the severe destruction of the leaf tissue! These insects have no mercy.
Lily Leaf Beetle. It just goes to show you that this pest can destroy a plant within a few days.
Keep your eyes open in the garden – you never know what’s hiding behind that leaf! Keep reading this blog for more info.