Matt Ritter's Advise on Tree Leaves to Use As Toilet Paper

Cal Poly Botany Professor Matt Ritter's Blog entry last week goes over a list of tree leaves to use as toilet paper in an emergency. I don't know if has tested these, and remember if you have an allergy to any of these trees this practice could really ruin your day.

What's Blooming Now at the Arboretum Smartphone Google Earth Tour 3-7-2020

Just aim your Google Earth equipped smart phone's QR code reader at this image

and you'll bring up a Google Earth tour of what's blooming now at the Arboretum! 

Here's the link to the Google Earth project if you don't have a QR reader handy:
https://drive.google.com/open?id=1MRFwpX0C1CgRZeE0zyaLRfkexse2hCkK&usp=sharing

Outline for Marvelous, Miraculous Mulches: How Choosing the Right One Can be the Key to Gardening Success

1)      What is “mulch”?

a)      A layer, organic or inorganic, applied to the top of the soil around selected plants that aid in their survival and aesthetics.

i)        Survival

(1)   Heat Regulation

(2)   Water Conservation

(3)   Soil Building

(4)   Weed Control

(5)   Pest Control

ii)      Aesthetics

(1)   Path building

(2)   Artistic Elements

(3)   Landscape Elements

2)      What Isn’t A (very good) Mulch

a)      Fertilizer

b)     Manure

c)      Compost

3)      Survival

a)      Heat Regulation

i)        Reflects heat and sun away from soil

ii)      Soaks up heat

iii)    Wicks up moisture, the resulting evaporation of water off of the mulch cools down the soil below.

b)     Water Conservation

i)        Cooling properties keep evapotranspiration rates lower.

ii)      Cooling also keeps plants roots active –hot, dry roots don’t work very well.

(1)   80% of the roots of most plants are located no deeper than 18 inches deep.

iii)    Reflective cooling mulches reflect heat and light off of the soil. Ex. Plants next to rocks growing better than those not.

iv)    Evaporative cooling mulches dry out more slowly than hard soil surfaces. This slow drying stretches out the evaporative cooling effect of the drying mulch, cooling the soil surface and the roots below.

c)      Soil building

i)        Mulches provide unique compounds to the soils around the plants that help the biological organisms in the soil that are helpful to the plant.

ii)      Bark contains tannins, phenolic and other compounds that break down slowly in the soil and can help lower the pH of the soil to that more favorable to plants. These compounds can be chelating agents as well and may be necessary for the health of beneficial soil organisms.

iii)    Just the cooling and water conserving nature of mulch helps plant friendly organisms thrive in the soil.

d)     Weed Control

i)        Mulch acts through several mechanisms to keep weeds down.

(1)   Physical

(a)   Seeds cannot get down to the soil level to germinate.

(b)   Seeds germinate and then dry out because of the air circulation between mulch particles

(c)    Barrier –lasagna mulching prevents weeds in part by keeping the newly germinated plants from reaching air and light.

(2)   Bio Active

(a)   Mulch has or creates natural herbicidal compounds

(i)     Lasagna Mulching (bio active?)

1.      A layer of moist green waste sandwiched between two layers of cardboard (or one layer on top if heavy clay).  On top is a layer of traditional mulch.

2.      The green waste decomposes and forms herbicidal compounds that kill weeds and propagules.

3.      After a period of time desired plants are planted through the mulch and the top layer of cardboard.

(ii)   Rice Hulls: a similar method using plastic and rice hulls is used by strawberry growers to replace now banned soil sterilificants (like Methyl Bromide).

e)      Pest Control

i)        Many types of mulch provide cover and ideal conditions for various insect predators.

ii)      Many types of mulch also provide conditions repellent to pests & diseases.

(1)   Snails can be repelled by rocky, dry mulch.

(2)   They can also be repelled by sharp mulches.

(3)   Pecan hulls are used around Camellias to repel snails AND they have an anti-fungal effect on Camellia Bud Blast.

iii)    Mylar reflective mulches can be effective pest control.

(1)   Light reflected on the dorsal side of leaves and flowers confuses insects like aphids that prefer to start their infestations on the shady part of their hosts.

(2)   Light can also make pests more visible to predators.

(3)   There’s also the added benefit of more light for photosynthesis.

iv)    Straw –keeps fruits off of the ground, safe from fungal infestation.

4)      Aesthetics

a)      DG, gravel, and other mulches can be structural and aesthetic, as well as beneficial to plants.

i)        DG

(1)   Great for paths and, in larger meshes, great mulch for most native plants.

(2)   A layer of DG over a properly created convex path makes a good walking surface and will prevent many weeds from growing on the path. Sealing  the DG path is also a good idea.

ii)      Different sizes of Fir or hardwood bark make good paths as well, however make sure the soil under them is compacted well and inspect for weeds regularly. Bark decomposes significantly in a year or two and you might have to add more.

(1)   Stay away from colored bark.

(2)   Stay away from wood chips.

iii)    Gravel.

(1)   Can purchase in different colors

(2)   Can be purchased in different sizes.

iv)    Volcanic cinder rock.

(1)   For a dark colored look.

(2)   Tough for weeds to get a start in it.

(3)   Can be too hot for plants due to the dark color absorbing more infrared light.

v)      Tumbled Glass (and shattered safety glass)

(1)   Comes in many colors.

(2)   Can be used to create stripes, patterns, even pictures that are fairly long lasting.

(3)   Can be lit from below for an added effect.

vi)    Stay away from: Mulch made from old tires, plastic sheeting that is not reusable, and especially –Stay Away From Weed Block Cloth (Unless you prefer using a jackhammer to remove it).