Frequently Asked Questions
About
Rain Bird® Irrigation Supplement
1. What is Rain Bird Irrigation Supplement and how does
it work?
Rain Bird Irrigation Supplement (RBIS) is 100% natural consisting
of 98% water and 2% cellulose. It is not a polymer and is
harmless to people and animals. The water in RBIS is released
by a natural process where the cellulose is gradually broken
down over time by micro-organisms found in soil. As RBIS
liquefies the capillary activity in soil carries and maintains
moisture throughout the root zone for an extended period
of time. The use of RBIS allows the plant continuous moisture
while avoiding being too wet or too dry when recommended
quantities are applied.
2. Is it safe to eat Rain Bird Irrigation Supplement?
We do not recommend this, however, in the event of accidental
ingestion RBIS is 100% natural and harmless to people and
animals.
3. Does Rain Bird Irrigation Supplement change the pH of
soil?
Laboratory tests have conclusively shown no significant
shift in the pH of soil from RBIS.
4. Is it possible to over-water using Rain Bird Irrigation
Supplement?
When applied at the suggested usage, RBIS will not over-water
plants. The rate at which RBIS liquefies is based on several
factors such as levels of micro-organisms in the soil,
ambient temperature and the amount of RBIS surface area
exposed to
soil. Following the directions for applying RBIS, each
quart carton or 3” tube & gel pack will provide
moisture for a period up to 90 days.
5. Does Rain Bird Irrigation Supplement freeze?
Yes, however, when temperatures rise above freezing RBIS
will thaw and return to its normal gel state without loss
of product or product effectiveness.
6. When temperatures are higher will Rain Bird Irrigation
Supplement turn into liquid more quickly?
Yes, temperatures significantly impact the rate of water
release of RBIS. In tests performed by the University of
Arizona constant thermal regimes of 15°, 25°and 35° C
showed water release rates doubled as the temperature increased
from 15° to 25° C and then doubled again between
25° and 35° C. Water release increased about two
fold for each 10°C increase in soil temperature which
means water release at 35°C is roughly four times that
at 15°C.
The fact that water release from RBIS varies so much
with temperature is not found to be a negative characteristic.
In many parts of the world evaporative demand (evapo-transpiration)
varies by a factor of four or five over the course of the
year. Evaporative demand is lowest during the coolest months
when soil temperatures are low and highest during the warmest
months when soil temperature approach peak levels for the
year. The relationship between water release and temperatures
allows RBIS to ‘Flex” to season changes in
evaporative demand and is considered a desirable feature
of RBIS. Due
to this fact it is recommended that the user check the
product between 45-60 days.
7. Can I fertilize while using Rain Bird Irrigation Supplement?
Yes, direct contact of RBIS with fertilizers will make RBIS
liquefy more quickly. It is important to note that if you
are fertilizing, you may want to check the RBIS between 45
and 60 days.
8. Do plant roots grow up into the Rain Bird Irrigation container?
No. A plant does not recognize RBIS as water while it is
in a gelled state.
9. Do the roots of the plants develop and grow unevenly
around the area the Rain Bird Irrigation Supplement has liquefied?
No. With most plants it is recommended to use two or more
containers of RBIS around the plant, supplying equal distribution
of moisture around the root mass at the onset of root development.
As the plant is establishing and needing more moisture the
root structure will grow naturally as the plant seeks out
a moisture source.
10. How can the recommended quantities of RBIS called for
give a plant enough moisture to grow, thrive and establish
a root system when the evapotranspiration (ET) rate of
the plant is considered greater then the amount of moisture
delivered by RBIS?
There are two main applications for RBIS. One is to deliver
the necessary additional moisture that is required for plant
establishment to a newly planted ornamental tree or shrub
within an already established irrigated garden or turf area.
In this case the plant is receiving adequate moisture allowing
for evapotranspiration through both the leaf structure and
the soil.
The second function of RBIS in a transplant situation
is to establish a native plant without receiving additional
moisture other then natural precipitation. In this event
two things happen. The first is that the plant goes into
a state of deficit irrigation which means that it is not
receiving enough moisture to grow new leaves, fruit or
flower.
(See reference below) When this happens the plant compensates
by synthesizing the hormone abscisic acid, which triggers
closing of stomata, thus reducing water loss through the
plants leaves. The plant then focuses it’s energy
on root growth seeking a natural moisture source. With
this
type of RBIS application the moisture is directed at the
root mass allowing no transpiration of moisture from the
soil. This application is used where revegetation is called
for in areas too remote to set up traditional irrigation,
on slopes or in wildlife habitat.
Reference: Julian I. Schroeder, June M. Kwak & Gethyn
J. Allen
Cell and Developmental Bilogy Section, Division of Biology
and Center for Molecular Genetics, University of California,
San Diego, 9500 Gilman Drive, La Jolla, California 92093,
USA
Nature/Vol 410/15 March 2001
evapo•trans•pi•ra•tion
Pronunciation: i-'va-pO-"tran(t)-sp&-'rA-sh&n
Function: noun
Etymology: evaporation + transpiration
: loss of water from the soil both by evaporation and by
transpiration from the plants growing thereon
10. Once the Rain Bird Irrigation
Supplement has finished liquefying what do you do with
the quart, the 3” tube
or the square sleeve?
The quart carton is paper and printed in vegetable ink
so it can be left in the ground to degrade; this process,
depending on climate may take anywhere from 6 months to
one year. During the process of degrading the quart will
naturally fold into the hole and with natural weather occurrences
other soil and leaf litter will fill in the hole completely.
If you choose to take the quart carton out of the ground
and throw it away simply brush some of the surrounding
soil and leaf litter into the hole left behind.
The plastic sleeve or tubes are used in situations where
the plant requires three or more applications therefore meant
for re-use or re-cycling. As with the quart container, when
they are removed from the ground, brush some of the surrounding
soil and surrounding leaf litter into the hole left by the
container.
When you are using the tube or the sleeve over an extended
period of time, RBIS will leave a protective crust at the
bottom near the root zone keeping any air away from roots
until you are ready to reapply. It is recommended reapply
after a significant rain event to water through the container
and around the drip line of the plant when reapplying.
11. Does the liquefaction rate change when it rains or when
the plant is receiving additional irrigation?
Studies performed at the University of Arizona show that
soil moisture does impact the rate of water release from
RBIS. Water release was reduced significantly when soil moisture
was either very wet or very dry. In wet soil the release
was reduced by 33%; this reduction in water release at higher
soil moisture levels is important from a practical sense
because soils at higher moisture content (30% or above) contain
plenty of water for plants to uptake and are prone to losing
moisture due to drainage and thus would not need the additional
water from RBIS. If watering or rain events produce excessive
soil moisture, results from this study indicate water release
from RBIS will simply be reduced.
On the other hand if soil is too dry water release from
RBIS will be reduced by 40%. Failure to follow directions
and not water at the time of application could possibly result
in water stress or plant death. It is therefore important
to follow the planting instructions and RBIS application
instructions when first applying RBIS.
